What is the Safest-Shortest distance I am able to have for a Piston to Valve Clearance? I am trying to use a stock 5.7 ls1 and 317 heads they have work done not sure about how much it has been milled. I have a Trex cam
.608 .612 lift 238 242 Durat.

 

most people would recommend .080 IN .100 EX.
i dont think there is a max "safe" clearance you are looking for. rpm and valve timing will play their own role as well.
is it an automatic or manual transmission?

 

I don't think you have a Trex cam cause it has a 242/248 Duration . I hope you read up on the T-rex cam.

 

i think i have about .045 and that is way close....id like to be .080. is the cam in the car and running???

 

My mistake, yes i do have a trex cam. I have a manual, no its not in and running yet I do have the heads off. I want to install them but im checking the clearances 1st.

 

What type of work have you done to your heads. Secondly don't ever take advise from any one on PTV you need to do it your self because your engine is not their engine.

Here you go if you don't know how to do it yet. by the way .080 is the best distance.

http://www.racingheadservice.com/Inf...eClearance.asp