496 building advice needed
#21
Senior Member
RACING JUNKIE
Join Date: Jan 2006
Location: La.
Posts: 2,890
Originally Posted by rrrdad
yes it is a bit more than I want to spend bu that is a descent price.. What is the max CFM you can get out of stock heads? and do you know the max lift on stock heads? Thx MM
The heads now have 2.190 / 1.880 Manley Super Duty Stainless valves, full port work and the valve spring pockets are cut for 1.625 dia springs. The egr ports are filled. The head guy never did fill out a flow chart for the heads, but did say they flow 320 cfm on the intake @ .700 lift and 240 cfm @ .700 lift on the exhaust. About the only thing left to do to them is angle mill them. I've thought of doing it, but I think I'm done with them. I want to upgrade to a set of AFR 335 cfm heads.
Here is the flow charts for stock as cast AFR 325's, you'll note that they flow 384 CFM out of the box @ .700 lift. That's more than Brodix BB2 Extra heads flow fully ported. You can also see the heads cost $2200.00 from Jegs which make that deal even better on the RJ advertisment especially with extra parts.
http://www.jegs.com/p/AFR-Airflow-Re...56123/10002/-1
Zip.
#22
Senior Member
RACING JUNKIE
Join Date: Jan 2006
Location: La.
Posts: 2,890
Originally Posted by rrrdad
Abit off the subject but what is the max bore for a BBC... Found a block that is 4.382... I believe that is about the max.... You tell me?
The problem with the block you mentioned is finding pistons for it. It's not a standard over bore so you may have to have them made (EXPENSIVE) probably over $1000.00.
JMO
Zip.
#23
Junior Member
APPRENTICE
Thread Starter
Join Date: Oct 2004
Posts: 19
I agree. After spending most of the day on here researching I can see this is not the ideal block for me.. Right now we do have a basic 454 passenger car block that we will use.... good info and thank you
#24
Junior Member
APPRENTICE
Join Date: Apr 2006
Location: New Haven, CT
Posts: 16
Re: 496 building advice needed
Originally Posted by rrrdad
We are in the process of putting together a parts list for a 496 that will be in our dragster. I will have to use stock heads for the first couple years. I need advice on pistons, cams, lift and expected HP of this engine. Thx M