SuperFlow Flowbench 110
Instructions Section
1.0
Page
Flow-testing
description SuperFlow flow t e s t ? What testing Adapting heads Flow t e s t p r e l i m i n a r i e s
Performing
flow t e s t
s h e e t sample test data Analyzing Avoiding t e s t e r r o r s
Test data
Flow T h r o u g h E n g i n e s HP
CI
RPM
Intake
CFM
P o r t Area
Shape
12 16
Valve S e a t s
Valve S i z e s Valve L i f t
Flow
C o m b u s t i o n Chambers
22
Dynamic Flow E f f e c t s
23
Supercharge Effect
10.0
Inertia
11.0
T e s t Pressure Conversion C h a r t
12.0
Suggested Additional References
13.0
Troubleshooting
26
29
1.0 Flow-testing .1
Superflow 110 d e s c r i p t i o n
The Superflow 110
measure air-flow resistance designed engine c y l i n d e r heads, i n t a k e manifolds, v e l o c i t y s t a c k s , an r e s t r i c t o r p l a t e s . Fo intake t e s t i n g , drawn machine, through th c y l i n d e r head into through blower, and e x i t s through th o r i f i c e p l a t e to path Superflow 110. For.exhaust t e s t i n g , th air-flow is f r o n t c o n t r o l panel. switch on th reversed by ORIFICE PLATE
TEST
RESSURE Sl
HEAD
M[HR
BLOWER flOW
CONTROL
KNOB
The t e s t pressure meter (manometer) measures base of the t e s t c y l i n d e r . vacuum The
pressure t e s t pressure adjusted to i n s t a n c e 15.0 inches standard v a l u e , water, by turning th flow c o n t r o l knob on lower f r o n t panel. i n t a k e o r exh exhaust aust flow. Separate knobs c o ~ t r o l c o e~ i tt h r o el r flow i n c l i n e d flow meter (manometer). The amount read from pressure difference across th flow The flow meter measures to Superflow 110. orifices By s e l e c t i n g d i f f e r e n t
combinations
orifices,
flow meter can be used
ny
o b t a i n high accuracy over d i f f e r e n t ranges wide range flow range s e l e c t e d 100% flows. an The flow meter reads with rubber s t o p p e r s . .312" diameter and a 1.875" diameter s e p a r a t e t e s t o r i f i c e with included flow t e s t e r . calibration hole
The machine r e q u i r e s 110 VAC, an draws 15 amps.
110
VD
electrical
power
1.0 Flow-testing .1
Superflow 110 d e s c r i p t i o n
The Superflow 110
measure air-flow resistance designed engine c y l i n d e r heads, i n t a k e manifolds, v e l o c i t y s t a c k s , an r e s t r i c t o r p l a t e s . Fo intake t e s t i n g , drawn machine, through th c y l i n d e r head into through blower, and e x i t s through th o r i f i c e p l a t e to path Superflow 110. For.exhaust t e s t i n g , th air-flow is f r o n t c o n t r o l panel. switch on th reversed by ORIFICE PLATE
TEST
RESSURE Sl
HEAD
M[HR
BLOWER flOW
CONTROL
KNOB
The t e s t pressure meter (manometer) measures base of the t e s t c y l i n d e r . vacuum The
pressure t e s t pressure adjusted to i n s t a n c e 15.0 inches standard v a l u e , water, by turning th flow c o n t r o l knob on lower f r o n t panel. i n t a k e o r exh exhaust aust flow. Separate knobs c o ~ t r o l c o e~ i tt h r o el r flow i n c l i n e d flow meter (manometer). The amount read from pressure difference across th flow The flow meter measures to Superflow 110. orifices By s e l e c t i n g d i f f e r e n t
combinations
orifices,
flow meter can be used
ny
o b t a i n high accuracy over d i f f e r e n t ranges wide range flow range s e l e c t e d 100% flows. an The flow meter reads with rubber s t o p p e r s . .312" diameter and a 1.875" diameter s e p a r a t e t e s t o r i f i c e with included flow t e s t e r . calibration hole
The machine r e q u i r e s 110 VAC, an draws 15 amps.
110
VD
electrical
power
What
flow t e s t ?
simplest form, flow t e s t i n g c o n s i s t s o f blowing sucking constant through pressure. Then cylinder head various valve l i f t s . measured flow r a t e change can be made and head r e - t e s t e d . Greater flow i n d i c a t e s an imtests made under same c o n d i t i o n s , no provement. atmospheric conditions machine v a r i a t i o n s corrections are required. The r e s u l t s may be compared d i r e c t l y .
At
possible to a d j u s t an c o r r e c t o t h e r extreme, an v a r i a t i o n s so t h a t t e s t r e s u l t s ma be compared those o t h e r head, t e s t e d under an conditions on an o t h e r Superflow Further c a l c u l a t i o n s ca be made determine valve machine. e f f i c i e n c y and various recommended port lengths and cam timing. very cumbersome without small,electronic The c a l c u l a t i o n s square r o o t key. c a l c u l a t o r , preferably with The c a l c u l a t i o n s simple flow t e s t i n g . essential Adapting heads
testing
mounted onto Superflow by means of cylinder Cylinder heads tube 4" long with same adaptors. The adaptor c o n s i s t s o f engine and a flange welded on each end. The lower flange bore bolted to the flow t e s t e r and th bolted upper flange t e s t c y l i n d e r head. The flanges must be f l a t clamped make an a i r t i g h t s e a l . The adaptor tube may be 1/16" gasketed In some cases l a r g e r or smaller than th actual engine c y l i n d e r . make he upper flange adaptor about 20% convenient wider than head w i l l be supported t e s t c y l i n d e r head so t h a t th testing when end c y l i n d e r s . offset open the valves device must be attached to he c y l i n d e r head to the various t e s t p o s i t i o n s . The usual method attach bolt en rocker arm stud that threaded DQUnt rotated, end contacts th valve stem. As bolt valve. A .001 d i a l i n d i c a t o r may be 1" pushes open th valve spring contacting mounted to the same f i x t u r e with amount valve opening. The standard valve measure retainer springs should be replaced with l i g h t springs for t e s t i n g . Se Superflow brochure various types valve openers. photos
intake side of cylinder head, On strongly recommended radiused entrance guide be i n s t a l l e d lead the that straight into thick head. The guide should be about on p o r t width ness an be generously radiused on inside way down The intake manifold ca a l s o be used. The exhaust flow th head. ma e x i t d i r e c t l y from th head.
Flow
test
preliminaries
t e s t data ma be recorded on th standard Superflow form test, F-120 t e s t data s h e e t , (see sample). Before beginning record th head d e s c r i p t i o n , an measure th stem and valve stem valve area The diameters. valve area minus th area in square inches.
valve area Before i n s t a l l i n g o r i f i c e p l a t e onto
.785 (D valve
D2
stem
a d a p t e r , i n s t a l l only the standard t e s t Superflow. Install rubber s t o p p e r s direction Superflow an o r i f i c e p l a t e on i n t a k e . Close i n t a k e an exhaust flow c o n t r o l knobs knob lightly against their seats. test
Zero th v e r t i c a l t e s t pressure meter an l e v e l an zero the inclined flow meter. With only the small .312" diameter t e s t o r i f i c e open, intake flow c o n t r o l u n t i l th turn on th machine an slowly open t e s t pressure reaches 10 .0" The flow meter should now read water. (# range 45% approximately on 10.0 cfm o r i f i c e open on t o p ) . .4 flow flow This i n d i c a t e s within x 10 cfm cfm. working p r o p e r l y . t h i s reading, th machine 1 cfm
Now remove range) an cf
rubber stoppers from th o r i f i c e p l a t e (185 .312" an 1.875" diameter holes open both th Adjust test orifice. intake flow c o n t r o l again u n t i l Allow th machine t e s t pressure reads 10.0". warm up f o r s e v e r a l higher than the upper thermometer reads about 25 minutes u n t i l th lower thermometer. flow meter reading times 185 cf Multiply th under standard obtain !llt o r i f i c e ~ . w i l l be 153.2 cf flow meter does th read 153.2 cfm, th conditions. flow correction factor. have be c o r r e c t e d by readings w i l l equal This f a c t o r
Test flow c o r r e c t i o n f a c t o r - -- - - -- -
153.2
test
1f.
o r i f i c e flow
machine v a r i a t i o n s an atmospheric This factor compensates conditions. Fo Enter t h i s information on test data sheet. b e s t accuracy, t h i s factor should be determined before each d a y ' s does testing. need be re-determined before a d d i t i o n a l t e s t s same day. on th by th Multiply th correction factor to flow ranges on l i n e obtain c o r r e c t e d range, an e n t e r these in l i n e D on data t e s t s made on s h e e t . The c o ~ r e c t e d flow ranges ma be used same day.
Superflow w i l l draw 10" due Then: test p r e s s u r ~ .
Flow c o r r e c t i o n f a c t o r
lo
line
voltage,
137.0
t e s t o r i f i c e flow
8"
ll t e s t s should be performed th same r a t i o valve l i f t any valve diameter, LID r a t i o . Then th flow e f f i c i e n c i e s valves can be compared, regardless s i z e . Multiply the valve th obtain the valve l i f t LID r a t i o s diameter by each on l i n e s A and F i l l these data sheet. test points.
Choose from th
proper pressure for the intake valve diameter c h a r t b,elow. generally most convenient to t e s t t e s t pressure the exhaust valve th same t e s t pressure. F i l l th on line the data sheet.
Valve diameter 2.111
11
.3 to 2.05 11 l e s s than 11
Test pressure 11
1011
15"
This completes preliminary preparations. While they test results very time consuming, they w i l l insure t h a t be th v a l i d and r e p e a t a b l e . Most preliminaries w i l l quired subsequent t e s t s th same head. Performing
Remove ,the
flow
test
o r i f i c e p l a t e from th machine and i n s t a l l t e s t head, th a c t u a l cylinder adapter, an valve opener onto th flow t e s t e r flow t e s t s . Set the d i a l i n d i c a t o r read with the valve closed. Install either an intake p o r t . intake manifold i n l e t guide on th test
v e r t i c a l t e s t pressure meter and zero an level inclined flow meter. Close th intake and exhaust flow c o n t r o l valves l i g h t l y a g a ~ n s t t h e i r s e a t s (d force they w i l l be damaged). Place 3 and 2. rubber stoppers into o r i f i c e s Turn intake. mode s e l e c t o r switch Zero
Turn on intake flow c o n t r o l u n t i l th Superflow and a d j u s t use. t e s t pressure meter reads the t e s t pressure you intend Because Determine th flowmeter and c h a r t . leakage flow from #1 o r i f i c e i s open, th flow meter reads 10 cfm 100%. only 47% would i n d i c a t e reading .4 x 10 cfm leakage flow efm. Leakage w i l l usually be from 1 10 cfm. there no leakage, the t e s t pressure may r i s e th meter. matter as long as the flow meter reads zero. The This does leakage w i l l a f f e c t th t e s t provided t h a t you c o r r e c t Turn your r e s u l t s . Repeat t h i s t e s t before th Superflow. Enter th leakage on l i n e th data sheet to be exhaust t e s t s . from cfm. chart subtracted Open the valve
.2 valve diameter. th head Remove lift flow o r i f i c e s and turn on four rubber stoppers from 10.0" flow Superflow. Adjust th pressure allow the machine to warm up be minutes. This s t e p may omitted th Superflow has been warmed up previously.
The flowmeter
flow designed with multiple ranges so t h a t ca be measured very a c c u r a t e l y . g r e a t e s t accuracy, se o n l y o r i f i c e ranges which g i v e readings above 70% th scale. reading exceeds 100%, switch next h i g h e r range shown combination on flow c h a r t by changing o r i f i c e s open to th yo have previously determined the Superflow. proper flow ranges, f i l l line 5 and skip the next s t e p . not, open l i f t points. valve to f i r s t of the
select proper flow range, begin with the l a r g e s t stopper flow o r i f i c e s u n t i l flow r e - i n s t a l l th stoppers an orifices the proper number meter reads above 70%. This same t h i s t e s t p r e s s u r e , head, an valve l i f t . Always us To
c h a r t on th t h i s p o i n t . From future t e s t s front of machine, determine the f u l l s c a l e range v a l u e , then record the corresponding c o r r e c t e d flow range from l i n e D on l i n e recommended value an record th 5. Re-adjust th t e s t pressure th the temperature d i f f e r e n c e flowmeter an readings between to an bottom thermometers o n t o t h e Superflow F-120 machine. Go th next valve l i f t an data s h e e t . Turn l i f t may repeat require above s t e p s . (Each valve different Continue t h i s p r o c e d u r e u n t i l yo have reached flowmeter r a n g e . ) th maximum l i f t t e s t p o i n t .
mode s e l e c t o r switch exhaust p o r t , turn exhaust an close intake flow c o n t r o l valve. Move the valve opener the exhaust valve and r e p e a t above pro an d i a l i n d i c a t o r cedures. This completes test.
To
test
or intake manifold t e s t s , remove guide radiused :\'1let with replace intake manifold. intake t e s t s Repeat an determine th an compare results effect inta"ke manifold.
TEST
Test Description:
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Intake valve
DATA
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T e s t p o r t number
11
215
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Test p r e s s u r e ( i n . ) Valve l i f t ( i n . )
Carr.
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SAMPLE
Test
HeAP #
C!I£V
d.
e Intake valve /.
1-.
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-
-
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l_
4
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-
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I.
-STaJ(
N.
,
~
-
-
..
-
l.
--
,'·H-
Exhaust valve
'No - : - ~ n : x J ( .
~ , ~ ~ - i -
..
+
6:7-
R:Rrdate
-1
-t.-;.:.~
, , ~ - ! -
Q.
SrDcI(..
~ / 7 Z . B ~
-
~
-
-
-
+
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+
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r
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+
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7
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+ - - - - 4 - - - - ~ -
- - - ~ - - _ + - - - - ~ -
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- - - ~ - - ~ - - - - + _
- - ~ ' - - - ~ - - - - +
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t e s t data
Analyzing
Fo simple a n a l y s i s test results, only necessary c h a r t cfm, c a l c u l a t e th t e s t cfm, l i n e F i r s t calculate by multiplying the line meter reading, line 6, times th corrected flow range. Then s u b t r a c t leakage cfm, line from l i n e 7. The r e s u l t This line ! ! ! ! cfm, line 9. be compared to other t e s t s without f u r t h e r c a l c u l a t i o n s . passing To c o r r e c t for the temperature difference caused by th blower motor, th t e s t cfm must be multiplied by th through temperature difference factor shown bel ow. The temperature difference th d i f f e r e n c e between th upper and lower thermometer
readings.
Temperature Difference Correction Factor
50
10
.996
.992
Diff. Intake
15
20
25
30
35
40
45
50
55
.988
.984
.981
.977
.973
.970
.966
.962
.958
Exhaust 1.004 1.008 1.012 1.016 1.019 1.023 1.027 1.030 1.034 1.038 1.042
The r e s u l t fficiency,
line 12 corrected t e s t cfm. To obtain th valve flow calculate necessary pe sguare inch valve area and then compare t h a t achieved. best square inches o b t a i n l i n e 13 Divide l i n e 12 by the valve area Then f i l l chart section 7, figure 6. Divide l i n e 14 from l i n e 13 by l i n e 14 and multiply by 1 0 0 ~ to obtain l i n e 15 rating.
The percent flow rating can be used as an i n d i c a t o r o f th flow. futher improvements
room
left
These r e s u l t s
an a l s o be p l o t t e d on th graph printed on back each t e s t data sheet (see sample). The arrows shown i n d i c a t e th data used to i n d i c a t e s c a l e t o which plotted. Circles th exhaust t e s t p o i n t s . intake t e s t points and t r i a n g l e s
Many a d d i t i o n a l f a c t o r s an r e l a t i o n s h i p s .0 through 10.0 which follow.
discussed
sections
Avoiding Test Errors
Each t e s t you make involves considerable e f f o r t on your p a r t , an this effort be wasted yo allow undetected e r r o r s creep into your t e s t program. Always check the following p o i n t s to reduce th chances mistakes. Always us same o r i f i c e range same t e s t p o i n t . Keep th leakage CFM to a minimum by making a good s e a l on head. s u r f a c e s , including th valves l i g h t valve springs are used, make sure the valves are sucked open by th vacuum intake t e s t s . Always l e v e l and zero the meters before each t e s t . Always se flow i n l e t guide on intake side of head and always us same guide and c y l i n d e r a d a p t e r . Tr to conduct your t e s t s when t h e r e no frequent changes l i n e v o l t a g e . Voltage changes w i l l a f f e c t the accuracy Superflow, but they w i l l cause surge and be u n s t a b l e . with conduct n e a r l y p o s s i b l e , tests same equipment, As th used same way and same temperature. When tests. you d o n ' t same doubt, r e p e a t results,
s t a r t over.
10
.0
AIR
FLOW
THROUGH ENGINES
The horsepower amount an engine i s d i r e c t l y proportional to drawn i n t o cylinder an r e t a i n e d u n t i l i g n i t i o n occurs. intake and exhaust t r a c t , flow r e s i s t a n c e By reducing increased cylinder f i l l i n g i s improved and engine horsepower directly. The average airflow through each engine cylinder ca follows:
Average airflow (cfm) -
The intake airflow r a t e
average airflow for th total cycle. only 40% th
Fo pe
example,
cylinder
HP pe
be estimated
cylinder
times single cylinder w i l l be about cylinder because intake occurs during
Chevrolet V-8 engine produces 440 HP
55 HP.
Average Airflow Avg. Intake Rate Peak Intake Rate
HP
55 HP .. 88 cfm .5 x 88 cfm 0 cfm 220 cfm .. 550 cfm .5
operating, the pressure drop across the cylinder When an engine head ranges from 0 up 550 cfm about 145 inches water t e s t pressure reading on th (This equivalent flow r a t e . Super flow.
Th
about 23 inches about 2" average pressure drop water 220 cfm flow r a t e . When t e s t i n g with the Superflow, mercury) th t e s t pressure 0, 15 important whether same pressure used each inches water used, provided A head subsequent t e s t t h a t w i l l be compared th o r i g i n a l t e s t . t h a t measures 10% b e t t e r a t water t e s t pressure w i l l a l s o inches water. 145 inches measure 10% b e t t e r 10 23
The exception
this rule through small, lower valve l i f t s Then he t e s t pressure must be kept above long passages. certain minimum insure t h a t th flow remains turbulent and does slow down and become laminar. The minimum recommended pressures as follows:
Minimum Valve L i f t
Minimum Test Pressure 15" water
.050" .100" .200" .300"
Conveniently, the bigger the opening, t e s t pressure.
8" water 5" water 3" water
lower
required minimum
11
flow-testing a r e f r e q u e n t l y confused by c a r b u r e t o r Beginners Presently th U . S . , most c a r b u r e t o r s rated flow r a t i n g s . t e s t pressure flow c a p a c i t y 20.4 inches water (1.5 carburetor on inches mercury), An 850 cf t h a t passes 850 cfm 20.4 inches However, you air at t e s t pressure water. manifold vacuum gauge on racing engine observe full throttle, only reads about mercury (7.8 inches you w i l l inches that t e s t pressure water). At inches same c a r b u r e t o r water, why c a r b u r e t o r r a t i n g s appear would only pass 49 cf air. This proportion engine requiraments. be Large c a r b u r e t o r s ma be tested and compared on Superflow, but only t e s t pressure of 1" water, reduced t e s t pressure. At th c a r b u r e t o r w i : l flow 22% rated capacity inches For example, 1" t e s t p r e s s u r e , a 660 cfm carb w i l l flow mercury. .2 x 660 145 cfm.
.0
AIR FLOW THROUGH ENGINES (Cont'd) The amount power be gained by improved a i r - f l o w depends on e n g i n e ' s volumetric e f f i c i e n c y (the percent the c y l i n d e r full). An engine with 60% volumetric e f f i c i e n c y ca be improved more than an engine with 90% volumetric e f f i c i e n c y .
--------------------------------r-----
ENGINE
3000
YOLUMETRIC
cooo
The volumetric e f f i c i e n c y
EFFICIENCY
5000
6000
7000
be estimated as follows:
gasoline
Volumetric E f f i c i e n c y
RPM
5600 x
HP
100%
RPM
Be sure displacement th cubic inches. engine you se accurate HP f i g u r e s . the volumetric e f f i c i e n c y on an RPM f i g u r e s a r e probably HP un-supercharged engine exceeds 130%
where
error.
Fo
alcohol burning engine,
formula
Volumetric E f f i c i e n c y
0
HP RP
ern
100%
HP
RP
CID
CFM
HP
related RPM, CID an engine a i r - f l o w capacity wide spread use of accurate engine d e f i n i t e fashion. With dynamometers an flow-benches, ha become possible measure racing engine and then air-flow potential of predict maximum which he HP w i l l peak. Th e f f e c t p o t e n t i a l HP an RPM porting and manifold changes ca be a n t i c i p a t e d advance and proper take f u l l advantage camming changes made differences. gasoline engine determines The t o t a l air-flow thru maximum HP. At peak power, a racing engine w i l l us 1.67 cubic f e e t (cfm) pe develops. Fo example, 10 minute each HP HP engine w i l l us 167 cfm. This w i l l hold t r u e an four-cycle gasoline burning racing Alcohol engines w i l l use 1.47 cfm HP e n g ~ n e .
To increase a i r - f l o w capacity engine power output, e i t h e r th a i r - f u e l charge must be burned engine must be increased, or more e f f e c t i v e l y . Racers have tended concentrate primarily on air-flow. creasing To pu more intake manifold an
hundreds heads,
Th
flow r e s i s t a n c e thru an engine, carburetor, cylinder head must be reduced. This need ha a f t e r market c a r b u r e t o r s , manifolds and ported out cylinder more designed thru the engine.
a measurement device designed a i r - f l o w capacity of various engine components. Ai flow-bench
measure blown, standard pressure, and then th sucked, thru intake system a i r - f l o w capacity measured. t h i s manner, d i f f e r e n t p a r t s compared and effect changes an be quickly evaluated.
be
conducted These flow t e s t s velocity constant peak between and While flow-benc 100 400 feet per second. valve, usually varying as does velocity have shown t h a t flow-bench t e s t s a c t u a l l y simulate engine operation c l o s e l y enough. why flow-benches have become a major development tool This engine manufacturers and racers a l i k e .
But w h a t ' i s the" r e l a t i o n s h i p between
capacity on he flow bench engine? Tests have shown t h a t and th horsepower complete intake system a i r - f l o w measured maximum valve l i f t and test well developed racing engine w i l l produce pressure 10 water, follOWing HP er c y l i n d e r : .4 :::
x (cfm
10"
water)
13
Of course
maximum reach t h i s l e v e l , th engine must a l s o have r i g h t cam, an compression, short, tuned exhaust system. must be well-tuned racing engine. With t h i s formula, head-porter he improves maximum flow thru can see t h a t intake system by cfm, th engine w i l l gain .4 HP only cylinder. (The formula g a s o l i n e 4 - s t r o k e engines without super-chargers).
The i n t a k e system flow a l s o determines engine w i l l develop peak HP: 4.
...
PM
2000
(cfm
CIT>
which th
he RPM
racing
water)
10
where CID
er c y l i n d e r . Fo engine displacement cubic inches s u p e r - s t o c k and engines which a l l - o n t r a c i n g engines, peak power w i l l occur i n d i c a t e s , so use 2200 i n s t e a d than formula 10% higher RP
2000.
example. Now, l e t ' s t r y o u t these formulas on you have i n s u p e r s t o c k , "220 HP" small-block 292 Chevy which runs what w i l l be t e s t pressure what RPM? Tests show t h a t 10" th maximum HP air. The CID of water, t h i s intake system w i l l flow 105 cfm cylinder one-eighth 292 36.5 CID. HP
...
105 cf
.4
45.1
..
cylinders HP
2000
The
maximum powe racing e n g i n e s ) : RP
RP
So this
8
0;:
...
361.
45.1
HP
w i l l be (2200
2200 ':r03
super-stocks,
105 cfm
...
6330
RP
361 HP 6330 RPM. But remember, maximum potentai1 The engine w i l l only approach t h i s maximum p o t e n t i a l HP everything e l s e optimized. engine ha
another example Now, l e t ' s show how changes intake Fo t h i s example, we w i l l system w i l l e f f e c t engine performance. small block Chevy 302, displacement 37.75 CID cylinder. Intake Stock, 2.02" valve Normal ported, 2.02" valve Best ported, 2.02" valve Westlake, 2 1 . ~ ' valves
120 143 160 175
S ~ s t e m
cf cfm cfm cf
Power
Flow 41 49 550 602
HP HP HP HP
6360 7570 8470 9270
RP RPM
RPM RPM
14
The "Normal ported" head normally be about best t h a t However, achieved, even with c a r e f u l flow-bench t e s t i n g . possible improve " b e s t ported" l e v e l , though welding might head up be required. 8500 and engines must be wound up 9300 RPM a d d i t i o n a l flow. This brings us another g u i d e l i n e . engine must hold together need more than couple runs down drag s t r i p , th peak power should not be developed 3700 f e e t per minute. excess piston speed few runs down you want, t h i s l i m i t ma be raised strip 4600 fpm, but the engine w i l l need super i n t e r n a l p a r t s l a s t even one" run. Fo
l a s t two heads, th take f u l l advantage
These r u l e s peak be reduced simple formula th RPM more above peak HP): HP (remember, your s h i f t points may be 1000 RPM 5.
Safe peak power
6.
Maximum peak power
22.200 1n stroke
RP
RPM
27,600
stroke
e ~ p l e Returning now th 302 engine, well ported head would be adequate most road-race a p p l i c a t i o n s th 302 because th peak power s l i g h t l y more than th 3800 already being developed th power peak was pushed piston speed. an even higher RPM, engine would frequently f a i l t o f i n i s h race.
e x t r a breathing of the Westlake To take f u l l advantage 4-valve head, th power would have 9270 (4630 fpm) and would engine l i f e would be s h o r t . Without super i n t e r n a l p a r t s , The s h i f t point probably not survive even one ru down drag s t r i p . would be up around 10,500 RPM. fo any Chevy! th formulas t o g e t h e r , we p u l l possible Now, determining the maximum intake system flow required construct graph p a r t i c u l a r engine and a p p l i c a t i o n . From t h i s graph, you ca easily Remember t h a t s e l e c t th required flow an engine and RPM. th e n t i r e engine. CFM, CID and HP figures are for each c y l i n d e r , your engine and graph, determine To us CID pe c y l i n d e r an then you can read the RPM required p a r t i c u l a r HP and th CF a 10" t e s t flow c a p a c i t y t h a t w i l l be required on th flow-bench pressure.
16
an example, suppose yo have a 427 CID V-8 engine which w i l l 7500 RPM. From hold together up 53.4 CID (1/8 of 427), graph you ca tmprove your th m a x ~ power c y l i n d e r would be 85 HP 196 cfm on th flow bench 10 water t e s t pressure. intake system 7500 RPM. eight cylinders, Fo engine could produce 680 HP Fo
Of course i t ' . enough flow capacity stmply calculate an so l e t ' s t a l k about how required. The engine must achieve improve flow p o t e n t i a l an judge th engine a i r f l o w , an how engine. Intake Port Area and Shape
Fo
th i d e a l intake system would have a s i n g l e c a r b u r e t o r er cylinder with s l i d e - p l a t e t h r o t t l e and a v e n t u r i equal to Below .8 intake valve diameter. v e n t u r i , th carburetor times th open up s i z e of intake valve bore should gradually th intake intake manifold entrance and gradually taper down about .85 times th valve diameter point about 1/2" below the valve s e a t . The optimum port w i l l be discussed Section 9 . 0 . length maxtmum flow,
17
practice, this ideal does provide never achieved, but what an e f f i c i e n t port would be 1:f.ke. When porting ut guide-line maximum flow, keep mind. following points cylinder head
2.
4.
6.
d i r e c t i o n an decreases Flow losses a r i s e from changes v e l o c i t y (port bends an expansions). 1001. Port a r e a should be between 651. valve a r e a . Remove material primarily from outside of port bends, improve by increasing th radius inside. This bend.
Port length an surface f i n i s h important The g r e a t e s t flow loss tn the intake port du This makes expansion valve. th valve from 1/2" below 1/2" above th valve c r i t i c a l part port. s u b s t a n t i a l e f f e c t on The valve s e a t shape ha
flow.
th
area
most flow.
flow losses are caused by port expansions, not c o n t r a c t i o n s , yo may valve s e a t . The wonder why the port should be necked down below must both turn 90 and expand flows reason that the valve into engine c y l i n d e r . "Humping" port inward j u s t s e a t allows below make turn outward toward the valve t o t a l flow l o s s . Unfortunately, many edge more gradually, reducing th stock ports to large t h i s area already.
The c h a r t below shows approximately ~ h e r e flow losses occur stock Chevy head with 1.94" diameter intake valve. Note that port where negligible flow losses th s t r a i g h t p a r t o f easy to grind.
Source
Flow Loss
1 Loss
.1 Wall f r i c t i o n
.4-
push-rod Contraction Bend valve guide Expansion behind valve guide Expans ion, 25 Expans ion, 30 Bend e x i t valve
11
12 19 17
18
As manufactured, t h i s head flows about 8 3 ~ potential wedge-combustion chamber head. "The b e s t head p o r t e r s a r e able to aid of careful flow to about 9 S ~ crease p o t e n t i a l with Further improvements d i f f i c u l t without major surgery flow-testing. th Chevy port an welding. Grinding and enlarging the f i r s t 2 ~ ' where easy to reach ha very l i t t l e e f f e c t .
S.O
Valve Seats
The valve s e a t ha v a l v e , and guide th
three purposes: s e a l th p o r t , to cool th valve. Sealing and cooling thru promoted by a f a i r l y wide s e a t between .060" an .100". Maximum flow narrower s e a t , usually around frequently achieved with .030" wide.
Multiple angle good f u l l y radiused s e a t s essential t y p i c a l comgetition intake valve s e a t w i l l c o n s i s t o f flow. 30 to i n s i d e c u t .1SO" wide. .100" wide, a 45 s e a t .040" wide, and a 70 .060" wide, followed An exhaust valve w i l l work well with a lSo to by a 4S s e a t .060" wide, and a 7S inside The O.D. .100" wide. 4S s e a t . Flow-bench the valve should coincide with the outside of experimentation w i l l frequently uncover superior shape fo an p a r t i c u l a r head. simple 4S s e a t by up three angle s e a t w i l l out-flow 2S% lower valve l i f t s . .0
Valve Sizes
The t o t a l flow thru ultimately determined by engine valve diameters. While well-designed smaller valves w i l l perform l a r g e r valves on occaSion, geod, big valve w i l l always out-flow good, smaller valve.
Valve s i z e
limited by
Fo engine bore. wedge-shaped combustion chambers, p r a c t i c a l m a x ~ u m intake valve .52 times diameter bore diameter. Hemi-heads permit intake .5 valves up bore diameter due e x t r a space a v a i l a b l e times a l l , but the combustion chamber. Four-valve heads a r e b e s t engf.ne must operate extra very high-speed to take advantage valve a r e a . The present trend flow SO% 901.
diameter
racing engines keep th exhaust system intake system flow. This may be more than necessary. g e n e r a l l y no power improvement i n d i c a t e t h a t there Tests th exhaust flow long g r e a t e r than 60% intake flow. This would d i c t a t e an exhaust valve diameter .7 large .80 times as the intake valve.
19
Val ve L i f t and Flow
.0
The a i r - f l o w t h r u d i r e c t l y controlled by engine valve flow, greater The f a r t h e r the valve opens, l e a s t up lift. helpful order discuss a wide v a r i e t y valve s i z e s , point. valve diameter speak ratio terms valve l i f t of the valve r a t i o . Stock engines usually have a peak l i f t Racing engines open diameter, valves .3 even .25 d. .3
The graph
figure 4 shows how flow v a r i e s with l i f t well .1 controlled mostly by flow designed valve an p o r t . Up th valve an s e a t a r e a , flow peaks over and higher l i f t s th p o r t . Wedge-chamber controlled by .the maximum capacity finally masking an f u l l l i f t du bends, an intakes have lower flow 15% lower l e v e l . port-limited'
Valve p o t e n t i a l pressure 10"
Fig. 4.
IP M- It
test
flow water
li ....
....
....
so
,M- ..
...
..", ~ ' f "
....
tl'.
.E
~ ' I '
•• . ~ .
IJ
10 .,
r-
IJ
.10
.2
--
Valve lift II lame er
..
.3
r-
.40
be used Figure guide judging the performance an flow r a t e cfm p a r t i c u l a r valve, simply multiply valve. To cf pe square inch from valve c h a r t by th valve area minus The flow r a t e you not the "expected" flow r a t e , stem a r e a . maximum p o t e n t i a l flow r a t e test rather p a r t i c u l a r head some th popular heads pressure. The maximum p o t e n t i a l flow shown 10" th comparison c h a r t i n figure water t e s t pressure. These figures represent th maximum a i r - f l o w which be expected Even well modified under optimum conditions of port and valve s e a t design. heads w i l l g e n e r a l l y only ~ b t a i n 80i. these f i g u r e s . 90i.
Fig.
Maximum P o t e n t i a l Ai
Intake Valves
1200, 1.24" D. 50" D. Norton 850, Yamaha TX 650, 1.62" D. 72" D. Chev. Small Block, Chev. Small Block, 2.02" D. Chev. Westlake, 2x1.5" D. Ford 302, 2.25" D. Chrys Hemi, 2.25" D.
VW
.0 15.3 25.4 26.9 30.3 42.3 50.7 52.8 52.8
Flow
Valve Lift/Valve Diameter .2 25 15 .1 lU" t e s t pressure cfm
30.8 50.9 54.1 60.9 84.9 101.8 106.0 106.0
46.2 76.5 81.2 91.5 127.6 153.0 159.2 159.2
53.0 102.4
10B.7
104.8 146.3 204.B
182.6 213.2
56.6 109.2
115. B
112.0 156.2
21B.4
195.0 227.2
.30d 5B.9
112.5 119.0 162.7 225.0
203.1
233.4
you about designed ma wonder why some cams open valve f a r t h e r , even The answer open the valve more high t h a t i n order .3 and longer lower l i f t s , necessary maxtmum head-flow p o i n t . The e x t r a flow flanks gained on th th peak. l i f t pattern, flow reaches
maximum value
lift
Fig. The head-flow f i g u r e s shown 5 and 6 for the cylinder head alone with j u s t on inlet port. radiused i n l e t guide th When th intake manifold t o t a l flow w i l l drop installed from 3 0 ~ , depending on flow e f f i c i e n c y o f th manifold. each valve l i f t with an without the By measuring th flow take manifold, a c c u r a t e l y measure flow possible e f f i c i e n c y . Frequently, intake manifold w i l l have even more room fOf improvement than does total cylinder head. flow with intake manifold i n s t a l l e d which must be used formulas 3 and 4 described on pages 12 and 13.
21
Fig. 6
Valve flow p o t e n t i a l Fo
various t e s t pressures
herni-intake and
Valve Lift/Diameter Test Pressure
.05
exhaust valves
.10
.15
cfm pe
3" 5" 8"
12.2 13.6 16.7 19.2
10" 15" 20" 25" 28"
21. 5 22.8 25.8
36
15.0 19.3 24.4 27.3 33.4 38.6 43.2 45.6 51
.2
.2
.3
inch valve area 22.5 29.0 36.7 41.0 50.2 58.0 64.9 68.6 77
30.0 38.8
49
54.9 67.2 77 .6 86.7
91. 8 104
32.0 41.4 52.3 58.5 71.6 82.7 92.5 98.0
33.0 42.5 53.8 60.1 73.6 85.0 95.1
111
101 104
.2
.3
For wedge intake valves Valve Lift/Diameter Test Pressure
3" 5"
8" 10" 15" 20" 25" 28" 36
Valve area
.0
.1
cfm .6 12.2 13.6 16.7 19.2 21.5 22.8 25.8
15.0 19.3 24.4 27.3 33.4 38.6 43.2 45.6 51.8
.1
.2
inch valve area
er
22.5 29.0 36.7 41.0 50.2 58.0 64.9 68.6 77.8
25.7 33.2 42.0 47.0 57.5 66.4 74.2 78.5 89.0
27.5 35.5 45.0 50.2 61.5 71.1 79.5 84.0 95.3
28.6 37.0 46.8 52.3 64.0 74.0 82.6 87.4 99.2
.785 (D\a1ve
From a flow stand-point herni-shaped combustion chamber as valve l i f t reaches .15 valve c l e a r advantage over wedge. U n t i l higher l i f t s diameter, there l i t t l e difference, hemimost designs, the hemi-port also valve usually l e s s shrouded. s t r a i g h t e r -due an th valve angle. These two advantages ad up
higher l i f t s , even with equal valve average flow advantage 16% diameters. When yo consider t h a t herni-combustion chamber a l s o generally intake valve to be 10% g r e a t e r diameter than a wedge, permits herni-head racing engine. understand the success easy
.0
Combustion Chambers
appears t h a t most engines, combustion chamber design was valve geometry. Perhaps should be th dictated by th choice other wa around. Most combustion chambers j u s t d o n ' t combust as well generally they should. Hemi and pent-roof combustion chambers best with wedge chambers being 54 1 0 ~ worse.
Most gasoline burning racing engines use compression r a t i o between 12 and 13.5 completely f i l l e d , you th cylinder 1. would expect t h a t engine displacement would torque per cubic inch i s n ' t , an engine design. th differences be same, regardless mostly du to combustion chamber e f f e c t i v e n e s s . One wa
combustion chamber's performance measure judge torque output per cubic inch engine displacement. At th RPM peak torque, a good combustion chamber w i l l develop 1.25 1.30 foot pounds CID. high may be possible raise this torque foot-pounds CID, though without an outstanding combustion chamber design an ram-tuning. Most racing D e t r o i t V-8's only reach 1.15 foot-pounds CID. There room improvement. plenty
the required judging e f f i c i e n t burning second guide l i n e spark advance maximum power. The more e f f i c i e n t combustion chambers have higher turbulence and require less spark advance. t u r b u l e n t com" i g n i t i o n delay" time between bustion chamber s u b s t a n t i a l l y reduces spark f i r e s and th charge begins when burn r a p i d l y . smell-block Chevy with a normal combustion chamber Fo example, shape might require 42 BTDC maximum spark advance ( 3 5 ° . i g n i t i o n d e l a y ) , while highly turbulent combustion chamber might only r e q u i r e 33 BTDC advance (2 i g n i t i o n d e l a y ) . Th more turbulent chamber w i l l a l s o burn more rapidly and ,produce up same i n i t i a l 10% g r e a t e r power from charge.
Combustion chamber improvement more than science and so t r i a l and e r r o r methods frequently the only choice. general, distance from the spark plug high turbulence and minimize th strive th f ~ t h e ~ p a r t .of the combustion chamber. At times combustion chamber burning complexities ca make very compare cylinder heads on an engine. Fo confusing when trying stance, difficult compare a c y l i n d e r head on a Chevy 302 and same head w i l l b o l t onto both engines, then on a Chevy 330. While compression r a t i o , and combustion chamber e f f e c t i v e n e s s , and RP range w i l l change. Even degree turbulence w i l l change. These mask d i f f e r e n c e s due to the flow capacity factors heads and experienced engine b u i l d e r . confound even
Dynamic flow e f f e c t s be increased considerably Engine volumetric e f f i c i e n c y and power ca advantage by dynamic e f f e c t s which o c c u r during th intake c y c l e . Both k i n e t i c energy an th resonant pulses an be f i l l th harnessed volumetric e f f i c i e n c e s up engine c y l i n d e r limited to 130%. Without these dynamic e f f e c t s , volumetric e f f i c i e n c y 100% without supercharging.
When th i n l e t valve c l o s e s , pressure pulse bounces back intake t r a c t , an then By making intake a g a i n toward th valve. a r r i v e a t to proper l e n g t h , r e t u r n i n g pulse ca be timed t r a c t th de.ad c e n t e r o f th next intake c y c l e , shoving e x t r a an keeping exhaust gases out th To v i s u a l i z e what occurs, imagine intake p o r t . th t h a t on en placed a g a i n s t hard surface. steel struck with a hammer, a strong pulse ( t h e hammer blow) w i l l o t h e r en then back t o t h e hammer end. o t h e r end, an t r a v e l down th bar to Th pulse w i l l a c t u a l l y cause the bar to jump back towards hammer! (or the p o r t ) moves very l i t t l e , strong pulse While th has been t r a n s m i t t e d through To se t h i s p u l s e , i n t a k e p o r t must be th c o r r e c t length. The pulse w i l l help only through narrow range below RPM. Above c e r t a i n range pulse w i l l a c t u a l l y decrease power so proper synchronie s s e n t i a l . There be u s e d , zation a c t u a l l y s e v e r a l pulses which corresponding th th valve. 2nd, 3rd an time the pulse a r r i v e s pulse s h o r t e r . o t h e r s being weaker an best, The 2nd
Inlet pulsation chart
Fig.
Harmonic 2nd
Length formula
Lower
RP
97,000/RPM 74,000/RPM
RPM
Pulse Strength*
108% 104% 104%
89% 91% 93%
l32,000/RPM
Upper
Pulse s t r e n g t h v a r i e s with i n l e t flow an
10% no 4%
i n l e t valve opening
The c h a r t
Figure 7 shows be used. To o b t a i n pulses which RPM peak HP th i n l e t system l e n g t h , d i v i d e number shown by flow measurements (see S e c t i o n 3 . 0 ) . determined by th Fo example, 8000 RPM 2nd harmonic:
length
132,000 8,000
a:
16.5"
This d e s i r e d length from i n t a k e valve inlet entrance. th Fo engines with a plenum chamber type i n t a k e , the length valve from example w i l l b e n e f i t from 89% th plenum chamber. The pulse th up 108% 8000 RPM, from 7120 RPM up 8640 RPM. The g r e a t e s t above b e n e f i t w i l l occur a b o u t 3% below 8000 RPM. Below 7120 RPM "pulse w i l l a c t u a l l y work decrease engine power. 8640 RPM,
also necessary t h a t To obtain benefits from th pulsation, lift l e a s t 02 times valve intake valve be open 40 btdc a r e u s u a l l y diameter by 15 btdc. Openings 20 p r e f e r a b l e . The intake flow r a t i n g (see Section 10.0) must a l s o be 0.3 or g r e a t e r fo s i g n i f i c a n t b e n e f i t s . Inertia-supercharge e f f e c t
10.0
close, f a s t moving column t r i e s keep ramming i t s e l f i n t o th cylinder. i n l e t valve closed extra charge just right instant, w i l l be trapped cylinder ( c a l l e d i n e r t i a - s u p e r c h a r g i n g ) . be obtained. To determine Volumetric e f f i c i e n c i e s up 1301 maximum i n e r t i a - s u p e r c h a r g e , proper valve timing necessary i n e r t i a supercharge index, Z,and then determine valve closing timing can be determined from Figure 9. intake valve s t a r t s
When
Z depends on t h i s must be average i n l e t valve a r e a , measured. i n l e t flow valve l i f t F i r s t determine Next determine cam l i f t p r o f i l e complete intake system. From these two the valve versus th degrees engine r o t a t i o n . graph, as shown Figure data construct pieces engine flow engine r o t a t i o n . This c f m / i n ~ versus degrees plot t o t a l engine flow considering both the intake system and th cam •
_,1-
R: :-: :--1:-", -.'. -, ~ - :
80
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.....
;:
+ - - I ~ ~ - ~ . . , q . . . . . - + - _ - + - - _ ~ - - + " - ' _ - _ - _ · + I _ ~ _ : - : + j - . - · - + - - - - - ~ r - . - - I ... :·-··+-:-Ir.~~:-t-~:··----r ., :. .. : ... .
.
Count total
tained
th
number number
squares under flow curve an divide them l i n e . The number squares beneath th 87 i n t a k e system flow r a t i n g Cv.
Area under flow curve Total area under 87 cfm l i n e The C w i l l generally be between 0.35 an 0.45 ¥otal rating intake system flow Cv, better th engine. The average
valve area
inlet
Now t h i s data ca
inches
inertia-supercharge
CID I n l e t Length average i n l e t area
RPM
126,000
IC
i n t a k e valve a r e a .
Valve area
Cv
be used determine formula below:
index, Z, from
8.
Cv ttmes
th
average i n l e t area
good engines. This an engine. The higher
the displacement one c y l i n d e r i n cubic inches inches. i n l e t length
where CID
an
also w i l l u s u a l l y be between measure and 1 . 2 , an th strength i n e r t i a - s u p e r c n a r g e which w i l l be obtained. has been determined, o b t a i n th c o r r e c t Figure When i n t a k e valve closing angle where the v alv e should be closed down .1 lift valve diameter. th
1 . 4 P - - - - - - - ~ - - - - - - - - ~ 1 - - - - ~ - - ~ - - ~ - - - - ~ - - ~ - - - - ~ 1 - - ~ ~ - - ~
.--::--!--i _: __ 1.- ---- ---'1'-'-
1.3
'-
1.1
.-
--:.
- - - ' - - ~ + ~ ~ - : - ' 1 - ~ - ~ ~ ~ " ~ -
-. ,' -.,
.9
...
8
•
~
0
~
.
' t ., I
f ~ " ' i -; _
~
j.
..
____ .
-
-
..
1
...:..-. . :. _._.+ - ~ 10
~
~
1 - ' - - · ~ .....
-
.- I " , :
I
-:
, 1 ~ ~ ~ ~ : -"~-~~: -~~---. j: . 1 ' : - ~ ~ L ; ~ ~ - ;
..
- - ~ +
.--,-.
-+
1 -
--
- - - - ~ l - - - - -
~ ~ j - - -
'''-1
-,•
I
'TT
'-J
..
' :
------; j
....
• ,
I
i
.0
.
. I
I
f
t---:----'--:--·
---'1---;----
-+
1.2
I
!
-
-
-
~
~
- - ~ .
-
-
i ~
'"
-
-
~
~
~
~
-
..j-
-
•.
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~
-
-
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~
-
-
~
~
0
~
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0
ab
11.0
FLOW-8ENCH TEST PRESSURE CONVERSION CHART
Want
3"
...
CII
10
:I
3" 5" 7" 10" 12" 15" 20" 25" 28" 30" 35" 40"
45 11
5"
7"
10"
28"
30"
3.05 2.37 2.00 1.67 1.53 .764 .913 .683 .816 1.37 .592 .707 1.18 .S29 .632 1.06 .598 .654 .732 .845 .945 1.00 SO .483 .577 .632 .707 .816 .913 .966 .447 .535 .586 .655 .756 .845 .894 .418 .SOO .548 .612 .707 .791 . 837
3.16 2.45 2.07 1.73 1.58
1.00 1.29 1.53 1.82 .774 1.00 1.18 1.41 .655 .845 1.00 1.12 .548 .707 .837 1.00 .SOO
.447 .387 .346 .327 .316 .293 .274 .258
.64S
.577 .SOO
12"
Flow At:
15"
20"
25"
2.00 2.24 2.58 2.89 1.55 1.73 2.00 2.24 1.31 1.46 1.69 1.89 1.09 1.22 1.41 1.58 1.00 1.12 1.29 1.44 .894 1.00 1 . 1 5 1 . 2 9 .774 .866 1.00 1.12 .693 .775 .894 1.00
3S"
40"
45"
3.65 2.83 2.39 2.00 1.71 1.83
3.87 3.00 2.54 2.12 1.94
3.42 2.65 2.24 1.87
1.411.531.631.73 1.22 1.32 1.41 1.50
1.10 1.18 1.26 1.34 1.04 .12 1.20 1.27 1.00 1.08 1.15 1.22 .378 .926 1.00 1.07 1.13 .354 .866 .935 1.00 1.06 .333 .394 .471 .516 .577 .667 .745 .78 9 .816 .882 .943 1.00
.447 .422 .408
Example:
flow flow be cfm
15"?
65 cfm
1.73
FLOW RATE
Test Pressure
3" 5"
8"
10 12 15" 20" 28" 30" 35" 40" 45" 65" *Flow thru
t e s t pressure of
65 cfm
VS
what would
112.5 cfm
TEST PRESSURE
Peak Velocity 66.2 fp 114.7 148.0 187.2 209.3 229.3 256.4 296.0 350.3 362.6 391.6 418.7
444.1
533.7
JfCFM/In
27.6 cfm 47.8 61.7 78.0
87.1
95.6 106.9 123.4 146.0 151 .1
163.3 174.6
185.1
222.5
perfectly streamlined o r i f i c e with an area square inch.
12.0
Suggested Additional References I n t e r n a l Combustion Engine print.) (out
as Flow Annand
R o e , 1974
Haessner Publishing
(Search Engineering Library)
Theory I n t e r n a l Combustion Engine Practice, Charles Fayette Taylor, e d i t i o n , John W i l e y Sons,
(Search Engineering Library)
N . Y . , NY
I n t e r n a l C o m b u s t i o n E n g i n e s , Edward Obert, Edition, (Search I n t e r n a t i o n a l T e x t b o o k C o . , S c r a n t o n , PA
Engineering Library)
Sports Engine, Colin Campbell Robert Bentley, I n c . , (out print, Public Library) C y l i n d e r Head M o d i f i c a t i o n Theory and P r a c t i c e David V i z a r d , 1973, C l a s s i c Motorbooks, Osceola, I, order. c a l l (800) 826-6600 Tuning BL's A-Series Engine David V i z a r d , 1985. Haynes P u b l i s h i n g C o . , Lawrence D r i v e , Newbury P a r k , CA 91320 (805) ~ 9 8 - 6 7 0 3 , F ~ 1 4 - $ 1 9 . 9 5 .
S.A.E. Technical Papers
obtained S . A . E . T e c h n i c a l P a p e r s may contacting A u t o m o t i v e E n g i n e e r s , INC. Society Commonwealth D r i v e W a r r e n d a l e , P e n n s y l v a n i a 15096 (412)
Request
author
along
700122*
7 7 6 - ~ 8 4 1
number state C u r r e n t Year Catalog Send p a p e r title l i s t e d below . $3.50 each paper requested.
Research and Development High-Speed, High P e r f o r m a n c e , S m a l l D i s p l a c e m e n t Honda E n g i n e s Yagi
1970 720214*
Design Refinement of Induction Exhaust Systems using S t e a d y - S t a t e Flowbench Techniques
G.F. Leydorf,
1972 790484*
An
Analysis
Characteristics
Using
Feb.
Volumetric Efficiency stroke Cycle Engines
Mean I n l e t Mach Number.
March 1979
I t a r u Fukutani E i i c h i Watanabe
820154*
AirFlow through Poppet I n l e t Valves Analysis S t a t i c , Dynamic Flow C o e f f i c i e n t s
Feb. 1982
820410*
I t a u r u Fukutani E i i c h i Watanabe
A Study
Gas Exchange Process Simulation Automotive Multi-Cylinder I n t e r n a l
Combustion Engine
Feb. 1982
by Masaaki Takizawa Tatsuo Un
Toshiaki Oue Tadayoshi Yura
Bosch Automotive Handbook from
SAE
P u b l i c a t i o n s , $12.95.
*All papers belonging S.A.E. covered u.s. Copyright laws and cannot reproduced w i t h o u t permission paying reproduce obtaining from S.A.E. Publishing D i v i s i o n .
SuperFlow r e s e r v e s
rights
t h e s e i n s t r u c t i o n s worldwide.
translation Reproduction t h i s work beyond t h a t p e r m i t t e d 10 S e c t i o n s 10 1976 o.s. Copyright without p e r m i s s i o n o f c o p y r i g h t owner u n l a w f u l . Request permission f u r t h e r information should SuperFlow C o r p o r a t i o n . addressed
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UG t : ND
SCALE
TROUBLE
seems measuring system, When t h e r e
Unplug elbows,
2)
SHOOTING YOUR FLOWBENCH
problem with following:
flowbench
b r a s s / p l a s t i c t u b i n g from m a n o m e t e r places). u n t i l they 3/4" nylon hex. with Then, unscrew elbows p o i n t assembly u n t i l
Unscrew e l b o w s from flush
3/4" toward
tubing.
Using spare p l a s t i c tubing p u f f o r suck i n t o each m a n o m e t e r e l b o w , making s u r e f l u i d r e s p o n d s zero smoothly. s e t t l e s back Reconnect Turn flowbench back tubing elbows.
MilE"
A ~ O O 1/:11.
TROUBLE
SHOOTING YOUR FLOWBENCH
problem with following:
seems measuring system, When t h e r e
Unplug elbows,
2)
flowbench
b r a s s / p l a s t i c t u b i n g from m a n o m e t e r places). u n t i l they 3/4" nylon hex. with Then, unscrew elbows p o i n t assembly u n t i l
Unscrew e l b o w s from flush
3/4" toward
tubing.
Using spare p l a s t i c tubing p u f f o r suck i n t o each m a n o m e t e r e l b o w , making s u r e f l u i d r e s p o n d s zero smoothly. s e t t l e s back Reconnect Turn flowbench back tubing elbows. problem data NO
exists, please helpful collect will
still
FLOW
next three t e s t s . e v a l u a t i n g your problem.
TEST
With SuperFlow's t e s t o r i f i c e p l a t e b o l t e d rubber stoppers tightly holes, switch intake mode. place finger over small hole Turn machine test plate. Slowly, with both h o l e s test orifice c o n t r o l until v a l v e p l a t e plugged, a d j u s t intake reach v e r t i c a l manometer. t e s t pressure H o r i z o n t a l flow s c a l e should r i s e s l i g h t l y , t h e n s e t t l e zero with machine running. back not, record R e p e a t this test exhaust. reading. LOW FLOW TEST
a b o v e e x c e p t remove f i n g e r from s m a l l h o l e reach slowly open i n t a k e c o n t r o l v a l v e u n t i l v e r t i c a l manometer. Record test pressure Shut Intake Control reading h o r i z o n t a l manometer. exhaust mode:-Valve. Repeat t e s t Same t e s t
HIGH FLOW TEST
e x h a u s t mode from should still last rubber stoppers, removing test. Start Turn exhaust valve machine-on bottom. open until t e s t pressure vertical manometer. Record flow meter NOTE: S o m e t i m e s flowbench w o n ' t test pressure. that case, adjust to record t e s t pressure Repeat t e s t Shut exhaust valve. flow r e a d i n g . Yo
I n t a k e mode.
After recording
471-1746 and
----
c a l l SuperFlow, flowbench customer s e r v i c e .
collected data,
(303)
Superflow 110 CHECK-OUT INSTRUCTIONS
M A C H IN E P L A C E M E N T Remove
ton.
Superflow not lift
panel. P l a c e Turn
from
shipping c a r
front plastic geges on Superflow level t a b l e t o p .
plug
switch
S u p e r f l o w in
INSTRUMENT CONNECTIONS
fluid i n s i d s t h e m a n o m e t e r s during clear plastic tubes have been disconvelves have been closed. R e e d
keep shipping.
nected
small flow me te r. Open
instructions both
SET-
metere
white ettech p l e s t i c fluid v e l v e s
valvee.}
valve s make sure they are open B. C h e c k extrs b l o w i n g g e n t l y I n t o e a c h valve. u s i n g t u b i n g plastic p r o v i d e d . If fluid c o l u m n length m o v e s en r e t u r n s f r e e l y . valve is open. Confour n e c t t h e f o u r flexible p l a s t i c t u b e s o n t o m e t e r Inlet tubes.
f lo w m a n o m e t e r . L e v e l b u b b l e level Is built I n t o turning n1I!lnometer screw near the left th is ma no m a ter clockwise loosen Reise lower
l e f t side
m a n o m e t e r until
level b u b b l e Is c e n t e r e d b e t w e e n
then re-tighten
screw.
merks.
D. T o z e r o
f l o w - p e r c e n t scele. loosen
slide
flow m e n o m e t s r
bottom
screw
scele
thumb
align
with the left
t h e r e d fluid c o l u m n .
E.
Zero
the
scele
manometer
rotating
test
verticel
pressure
knurled
bot
o f t h e scale.
OPERATION CHECK If you purchased cylinder heed adapter, flow bench baee plate mounted flat t e s t orifice plata. Remove
B.
is
plastic adepter.
a i x - i n c h a q u a r e t e s t orifice p l a t e 5/16" flow bench. Leave b o th th e 7/8" t e s t orifice o p e n . install bolts h o l e s in f l a t w a s h e r s in el f o u r c o r n e r s . M o u n t only
R e m o v e al r u b b e r s t o p p e r s f r o m o r i f i c e p l e t e o f th e flow bench. flow referring c h a r t . n o t e t h e t t h i s is
flow range.
