[Tom Vaught]

Post by Calvin Hill:

“Based on what you said, it would state that the as cast out of the box E-head flows right around 300 CFM @ 28

Calvin Hill
Hill Performance
708-250-7420"


Posted - 16 Nov 2010 : 12:45:47 PM Pontiac Street Performance (by Steve C)

"I think many will agree that for the most part independent flow bench testing on the heads pretty much agree with the stated numbers by Edelbrock. They (EDELBROCK) stated 275 cfm at .600" on the 87cc head and 286 cfm at .600" on the 72cc head. And the intake runner volume is reported to be 215 cc's. Many years ago my engine builder did a good valve job and clean up (no porting) on a set of 87cc heads and they flowed 288 cfm on his bench. My 87cc castings were ported to 313 cfm at .600" with not much effort or elaborate port work and my 72cc castings were 329 cfm with no offset rocker arm, nothing special. My 87cc heads easly supported 600 hp on a 462cid combo and the 72cc castings suported 699.9 hp on a 450cid combo (4.125 stroke)."

Using Stan Weiss Test pressure converter: 300 cfm at 28” of water converts to 284 cfm at 25” H2O.

286 cfm @.600” lift (72 cc Edelbrock head) tested at 25” test pressure (SF1020 calibration test pressure) times a 1.06 multiplier (25" test pressure converted to 28" test pressure) works out to 303 cfm.

So I was off by 3 cfm (too low). My bad.

Tom Vaught

PS Didn't you say that on your flow bench you only got 260 cfm at 28" test pressure. Sounds like a bench needs to be recalibrated.

Course maybe someone doesn't want to recalibrate the bench. If a bench says the head flows 260 cfm and the head actually flows 300 cfm, someone could claim a 40 cfm improvement in the flow and basically never touch the head (if the customer later flows the head on an accurate different bench).
Just thinking out loud.

[Stan Weiss]

Tom,
This is from back in 2008 and so Edelbrock may have revised it since then, but it does say 28" H2O.

Stan

[Motor Daddy]

Originally Posted by Tom Vaught

So I was off by 3 cfm (too low). My bad.

Tom Vaught

Inexcusable. This is a zero tolerance zone.

[65nss4spdGTO]

Tom,

Nice week of work here for you. I knew you couldn't leave it alone. You hate being wrong

I’ve had E-head customers who have brought me heads with flow data sheets stating what the heads flow.

Example : The claim to flow 305CFM, I test on my bench and the flow 285CFM, then I work the heads and when they leave my shop they flow 345CFM. So what would they flow on the original bench? I really don’t care as much about what they flow when they come in, it’s what they flow when they leave.

Would you like me to post the flow sheets with the shop information and who flowed them? Then I can post the sheet what they flowed when they left.

As a side note, anyone that wants to come to my shop and watch me flow the heads they are welcome to, no smoke and mirrors going on here.

Calvin Hill
Hill Performance
708-250-7420

[The Boss]

[mike leech]

not sure a war against calvin about flow numbers on stock e heads is worth waging. JMO

[T Syron]

Originally Posted by 65nss4spdGTO

Tom,

Nice week of work here for you. I knew you couldn't leave it alone. You hate being wrong

I’ve had E-head customers who have brought me heads with flow data sheets stating what the heads flow.

Example : The claim to flow 305CFM, I test on my bench and the flow 285CFM, then I work the heads and when they leave my shop they flow 345CFM. So what would they flow on the original bench? I really don’t care as much about what they flow when they come in, it’s what they flow when they leave.

Would you like me to post the flow sheets with the shop information and who flowed them? Then I can post the sheet what they flowed when they left.

As a side note, anyone that wants to come to my shop and watch me flow the heads they are welcome to, no smoke and mirrors going on here.

Calvin Hill
Hill Performance
708-250-7420

True story.

Bought these heads from a member that claimed that they were 305 cfm heads. I did have the flow sheets from the company that ported them that confirmed it. I installed them on my car with a roller cam car and went the best 10.79 @ 124. The next year I built a new motor with 6 more CIs, Calvin's 345 CNC heads and went 10.03 @ 132. Same intake, carb, weight 3700 lbs, rear gear, trans, but different converter.

I was more than happy with the end results.

Tom Syron

[pontsd]

I have been at Calvin's and flowed at least a dozen different heads with him, some of them flowed at other respectable non Pontiac shops to get baseline info and confirm what each shop told me. And the results were very close, no smoke and mirrors or bashing of other shops work .

I have watched Calvin do port work and he takes pride in it and that when he sends them out to a customer they will flow what he said , and also show it at the track.

It's refreshing to be able to ask questions and have them answered without be treated or talked down to , oh and have good time .......

It seems to me that at times we all forget this is suppose to be fun !

I would like to see more support for the Pontiac community , or at least less bashing of each other ideas, products, etc....


JMHO ,
Thanks

[BruceWilkie]

Edelbrocks site http://www.edelbrock.com/automotive_new/mc/cylheads/ currently posts RPM head flow numbers showing only for the #60579 87cc chamber heads. NO mention at what inch H20.

Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench
#60579
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 72 138 198 239 264 275 N/A
Exhaust 56 106 141 163 175 185 N/A

The flow numbers for the D ports show test flowed at 28" H2O.

Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O (4.15" Bore)
#61589
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 65 136 199 237 255 262 263
Exhaust 52 103 130 145 151 157 159


Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O (4.15" Bore)
#61569
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 64 139 200 235 249 256 258
Exhaust 52 104 131 145 151 156 157
* Springs Rated to .550" lift


Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28" H2O (4.15" Bore)
#61569 ( D-PORT 87cc Chamber)
Valve Lift .100" .200" .300" .400" .500" .600" .700"
Intake 64 139 200 237 251 262 266
Exhaust 53 99 131 151 160 165 167

http://www.edelbrock.com/automotive_...former_d.shtml

The Chevy small block rpm heads also show flowed at 28" h2o.
http://www.edelbrock.com/automotive_...erf_rpm2.shtml

They've done a lot more SBC motors than the other motors over the years.
I never saw Edelbrock post the Chevys at 25" h2o. I dont recall seeing that number(25) used for the Pontiac numbers either... I suppose I could have missed it. Perhaps Edelbrock at one time maybe had a misprint quoting 25" h2o?


My old catalog showed the RPMs at 28 " as well . I recall verifying that info to the data default numbers in my sim program

My notes from Pro-sim program gives 286cfm at .600" 28" h2O for #6059 72 cc version and 275 at .600" 28" h2o for the #6057 87 cc rpm head

Here are the conversions from 28"h2o to 25"h2o... according to Pro-sim conversion calculator which matches Stan's, Wallace's and Larry Lemeaux's calculators...

286 cfm at 28"h2o = 270.24 cfm at 25"h2o for 72 cc rpm head.

The 87 cc RPM head at 275 cfm at 28" h20 = 259.85 cfm at 25"h2o.

The #61569 D-Port 87 cc head at 266 cfm at 28" h20 = 251.35 cfm at 25" h2o

FWIW if 286 cfm at 28" h2o it would require a depression of 30.8075 in h2o to = 300 cfm

[65nss4spdGTO]

EHTTFMF!!!

Calvin Hill
Hill Performance
708-250-7420

[BruceWilkie]

Originally Posted by Stan Weiss

Tom,
This is from back in 2008 and so Edelbrock may have revised it since then, but it does say 28" H2O.

Stan

Stan thanks that is the catalog I had. (maybe still have?)

[Batman]

Originally Posted by 65nss4spdGTO

EHTTFMF!!!

Calvin Hill
Hill Performance
708-250-7420

Calvin I'm not weighing in on the decimal point conflict/calculator war, but I did want to take a brief moment to acknowledge your skillful and timely use of EHTTFMF! here

[Stan Weiss]

Originally Posted by T Syron

True story.

Bought these heads from a member that claimed that they were 305 cfm heads. I did have the flow sheets from the company that ported them that confirmed it. I installed them on my car with a roller cam car and went the best 10.79 @ 124. The next year I built a new motor with 6 more CIs, Calvin's 345 CNC heads and went 10.03 @ 132. Same intake, carb, weight 3700 lbs, rear gear, trans, but different converter.

I was more than happy with the end results.

Tom Syron

Tom,
It is hard to say because I do not know what the convertor changed did but that sound like a little over 100 HP increase.

Stan

[Tom Vaught]

Originally Posted by mike leech

not sure a war against calvin about flow numbers on stock e heads is worth waging. JMO

Don’t like people implying that I am lying, only reason why I am posting this.

Post by Calvin Hill:

“Based on what you said, it would state that the as cast out of the box E-head flows RIGHT AROUND 300 CFM @ 28

Calvin Hill
Hill Performance
708-250-7420" [/QUOTE]

Don't think I said that. I was posting that a "non ported head" would flow "right around 300 cfm at 28" H20. The assumption was even you would not waste your time flowing a raw head out of the box without a simple valve job performed on the head.

Think my number "300 cfm" is a lot closer to the Edelbrock stated flow graph vs 260 cfm that your bench read.
That graph was good from 1998 to the 2003 time frame. Last time I looked at the advertising (or bought a head from them).

Tom Vaught

[Scott Roberts]

Originally Posted by Tom Vaught

Don’t like people implying that I am lying, only reason why I am posting this.












Tom Vaught

So you turn around and imply Calvin is knowingly phucking customers....classy.

[BruceWilkie]

The 2008 catalog has different flow numbers through the lift curve than the early 90's info posted.

The 2008 catalog actually states the depression at 28" H20 vs no mention of depression in early 90's literature shown above.

See attached pdf below

Latest online catalog lists same flow numbers as 2008 catalog but doesnt state the depression. (yet uses 28" on the D-ports).

Open link
http://www.edelbrock.com/automotive_...erformer.shtml

Looks to me, the newer 2008 up heads ports were refined to improve low to mid lift flows which tends to bring peak flows down a bit or just level off earlier... though it might also get unstable at the old peak flow lift point of .700" (.100" higher) vs new peak flow lift at .600".

One would need a virgin early 90's head and a fresh 2014 head on same bench to verify these differences in numbers .

[Tom Vaught]

Did not say that, said he might need to check the calibration on his bench if it reads 260 cfm on a 300 cfm head. Even the correction for 25"water vs 28" water is not that far off or the differences in the E-heads over the years.

You seem to be the one stirring the chit over and over Scott, not me.

I made a statement, period, about e-head flow numbers, calibrations, and accurate numbers. No different than testing in the winter to get a different correction factor or soaking the floor with water to play the humidity game. It is all a game.

Tom V.

ps Thought the agreement was You would not directly respond to my posts which you have done now Bruce W. Did you forget that agreement?
I kept my end of the agreement.

[Rusty4cyl]

Hey Scott, Don't get me started on Calvin. I don't want to hear anything about him Period

[65nss4spdGTO]

Originally Posted by Rusty4cyl

Hey Scott, Don't get me started on Calvin. I don't want to hear anything about him Period

You need to grow a pair of balls...

If you had a problem with the work I did, pick up the phone and be a man about it. Instead you take every shot you can on a public forum hiding behind your key board.



Calvin Hill
Hill Performance
708-250-7420

[65nss4spdGTO]

Originally Posted by Tom Vaught

Don’t like people implying that I am lying, only reason why I am posting this. Tom Vaught

I never said you were lying.

I'm just saying you aren't as smart as you think you are.

Calvin Hill
Hill Performance
708-250-7420