CLASS RACER FORUM

CLASS RACER FORUM (https://classracer.com/classforum/index.php)
-   Stock and Super Stock Tech (https://classracer.com/classforum/forumdisplay.php?f=4)
-   -   carb. CFM ?'s (https://classracer.com/classforum/showthread.php?t=24288)

rod 03-07-2010 11:46 AM

carb. CFM ?'s
 
dusting my old AHRA stock class car off to go to the 'vegas super chevy race soon. since bracket racing is all tere is anymore....i will retain the car as is. it was legal [back in the day] to run any Holley carb.
so a bit of car background and then the question.
3550 w driver, 2.64 low 4 speed, 5.67 gear. 265 [+60=273]. old Holley single plane [300-1 maybe] currently running a 600DP.
the two quickest runs the car ever made [at two different tracks, years apart] were with a 750 DP. 'vegas is 2200', Bakersfield is 280'
the calcs show this engine needs a 600 CFM. are the calcs wrong, only ballpark, or are there other facts which influence the outcome?

thoughts/ideas?
thanks rod

Kegracing 03-07-2010 12:12 PM

Re: carb. CFM ?'s
 
Rod,

Most all calculations make the "assumption" of 100% efficiency. This is what causes some errors. Often what cars require and what they want are two different things. Your combo may only require 600 cfm, but is the 600 DP going to give you 600 good cfm? The 750 can do that a lot easier... While I am a stickler for matching a combo, as I have proven to myself over and over that more is not always better, this is not going out to left field. If you were talking about putting a 1050 on it, I would say no way. But a 600 to a 750 is a pretty easy to justify swap.

Put the 750 on it, and then jet it for the best performance. Just my opinion...

Good luck!

Ken

Pat Cook 03-07-2010 01:21 PM

Re: carb. CFM ?'s
 
Hey let us know what the outcome is, thanks.

Robert Simpson 03-07-2010 09:35 PM

Re: carb. CFM ?'s
 
Rod, I would stick with the 600, if you don't turn alot of RPM's 7500 and higher then it should be just fine. We run a super stock 265 with the wcfb and would love to have a 600cfm, LOL. Good luck and tell us your results, any pictures?


All times are GMT -4. The time now is 03:46 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2025, vBulletin Solutions Inc.
Copyright Class Racer.com. All Rights Reserved. Designated trademarks and brands are the property of their respective owners.