TopEnd setup and P2V clearance?
Thread Starter
Teching In
Joined: Sep 2017
Posts: 34
Likes: 4
From: Edinboro, PA
TopEnd setup and P2V clearance? Hello Guys, I need some help/advice/knowledge on my top end build. Mainly hoping some of you have experience with a build like this and can give me advice or info on what issues I may have or things I need to check etc etc. I have a stock LQ4 in my 84 corvette right now. I am acquiring all the parts for this build and so far, this is what I have:
Comp Cams 54-469-11 camshaft (231/247 @0.50, 0.617/0.624 lift, LSA 113)
.660 valve springs
Stock 243 heads (potentially milling them 0.020-0.030")
I would like to know if this combo will have any piston to valve clearance issues as it is. And also, whether or not I can mill these heads 0.020-0.030" and still not have piston to valve clearance issues. My goal being to raise the compression ratio of the engine somewhere between 10-11:1.
Any further recommendations are greatly appreciated as I am not hugely knowledgeable on these motors. Thank you in advance!!
Comp Cams 54-469-11 camshaft (231/247 @0.50, 0.617/0.624 lift, LSA 113)
.660 valve springs
Stock 243 heads (potentially milling them 0.020-0.030")
I would like to know if this combo will have any piston to valve clearance issues as it is. And also, whether or not I can mill these heads 0.020-0.030" and still not have piston to valve clearance issues. My goal being to raise the compression ratio of the engine somewhere between 10-11:1.
Any further recommendations are greatly appreciated as I am not hugely knowledgeable on these motors. Thank you in advance!!
TECH Apprentice
Joined: May 2018
Posts: 336
Likes: 47
I would be checking ptv clearance for sure...also depends on what head gasket you’re using....better safe than sorry. I milled my 243s down to get 60cc’s and ran a .040 cosmetic gaskets....cam had 630/615 lift and they would have kissed the pistons.
Joined: Jul 2007
Posts: 1,500
Likes: 177
From: ELSA, South TEXAS (956) 802-7700
The intake duration and lsa are what's critical. With 231 and 113 you will be okay with stock unmilled heads. Now since you cant add back once you mill, I would go with thinner Cometic .040 gaskets and measure.
