I have a stock Ls1 with a 232/232 .598 112 LSA and I want to Increase Compresion to stay close to 11:1
I got a set of cometic .045 Head Gaskets and I want to get the heads (241) milled but I don't know how much (.020 or .030) and if I'll need to change the Pushrods to 7.350 or stay with 7.400 ???
Any Help will be Very Apreciated !!!!

Thanks

 

T.T.T.

 

You'll have to measure PTV to make final decision.
I would measure with the Cometics and based on that measurement (intake/exhaust) decide on how much to mill while staying safe.

 

Thanks man !!! what will be a good safe clearance ??? and how do I calculate the preload on the pushrods ???

 

If you use minumum PTV clearances of 0.080 on the intake and 0.100 on the exhaust you should be good to go. Use this for any engine you build.

 

As mentionned .080 Int/ .100 Exht

As for the p-rods you'll need to measure with a adjustable p-rod checker and once you have the measurement at 0 lash you add .070>.080 preload on that if you're running stock lifters (or Comp 850-16 for that matter)

 

You could always give Patriot a call and order a set of stock casting 243 heads for about $400 and switch all your parts over to those.

 

Hey !!! aren't the valves bigger on the 243's ???

 

I think they are the same size as 241's or other ls1 heads

 

Forget it !!! To much trouble for a little gain... I'll just mill them 0.010 with the 0.045 Cometic Gasket so I'll not have any PTV problems or Pushrods to change... Thanks for your help anyway !!!

 

Listen to Predator Z. Measure how much clearance you have now and then design and build your next heads