I honestly have no clue how these compare and am looking for some insight. My engine came with my project car already assembled. It is a 455, .030 over with Edelbrock heads that have been ported.

Here are the #'s:



Poser

Here is a good chart for stock heads that you can compare to.

http://www.pontiacpower.org/ultimateflow.htm

Here's the flow on my stock 62's:
Intake(D) Flow (cfm) Exhaust(S) Flow (cfm) Exh. Int.
.100 71 74 .100 46 .63
.200 126 122 .200 84 .68
.300 153 155 .300 106 .69
.400 158 158 .400 124 .78
.500 162 167 .500 132 .80
.600 165 167 .600 140 .84


Can't beat those Edelbrocks!

I'm REALLY suprised the numbers on those edelbrocks aren't better! Especially if they were ported!

I ported a set of 6X-4 heads in my garage and go retty close to those numbers....actually better across the board on the exhaust numbers!

That is also a pretty big difference from port to port!

Mine flowed 258 int and 232 exhaust at .550 lift and was still climbing, but I didn't have them flow them above .550....wish I had! I had 2 chambers flowed and they were less than 3 cfm difference from 1 to the other.

Agreed the variance between the two runner sets seems a bit high.

Be careful when comparing flow rates from different sources.
You need to ensure the same correction factors (temperature, humidity, etc.) and pressure were used. Also, sometimes a lead in radius is used so the flow is not hitting a a sharp edge. And finally, sometimes a head is flowed at one pressure and then "correct" to another which loses accuracy as well.

I agree completely, Mike!

I found my flow numbers....my memory was close, but not exact.

Port I/E .200 .300 .400 .500 .600
1 I 147.5 193.2 233.2 248.0 258.5
1 E 121.0 165.4 197.0 220.7 232.4
3 I 147.2 194.2 234.5 247.2 256.2
3 E 119.6 163.8 197.1 222.2 233.6

They were slowed @ 28 inches of H2O and the intake port entries were smoothed with clay. The intake and gasket is port matched and I made sure everything lined up perfectly during installation.

Nice flow on the exhaust Drew! Whatya charge for port work?

Did you by chance measure the runner volumes after porting?