98Camarod

iTrader: (43)

I realize that there are many of us FI folks that use these 317 heads. At what point does it become the restriction? I'm going to be eventually building a forged 408 and doing a twin turbo gt70's build and I picked up some 317s with the dual comp cam springs.

How fast has anyone gone on stock casting heads vs ported?

eviltwin_1987

iTrader: (18)

you can find alittle info in here
https://ls1tech.com/forums/forced-in...ing-heads.html

ss.slp.ls1

iTrader: (36)

I was going to use the same heads, but I was advised to use a smaller chambered head like 243's to reach my goal, because when building a bottom end to a desired CR, it will be better to start off with a stock chamber (~65cc) head. Then when I decide to go with some better heads like AFR or TFS, the CR will remain similar. But if i use the 317 heads, I will always have to use 72cc heads, or else the CR will be way off switching to better heads.

98Camarod

iTrader: (43)

Thanks, I didn't see this thread

You would still be able to help with the compression issue with gasket thickness. What was your desired CR?

Aster

iTrader: (9)

I wouldn't fret too much over that. Many of the aftermarket castings like AFR have 72cc chamber options.

lazylongboarder

iTrader: (2)

I've got some badass 320 cfm 243's that I REALLY want to use with my F/I build but don't have money for dished pistons and will probably end up keeping them and using 317's to get my comp down.
I don't see the 317's as a limitation, just not as happy to hang in the high rpms as long as the worked 243's IMO. I'm a road racer though.

I've seen 317's put down MONSTER #'s +1000RWTQ. It wouldn't hurt to try them with GM MLS gasket's. The investment would be under $500 and would most likely not disappoint.