curious to get everybodys opinion. we was puttin togethor my ls1 and we used the playdough meathod to check ptv clearance and it measured out to be 43 thousandths and 50 thousandths. would this be a safe to run? its a stock ls1 with portd 241s and custom grind cam.

 

How big is the cam? I personally wouldn't run it that tight. The clay method is also very inaccurate and I would double check with a dial indicator.

 

Im in the exact same boat, its too tight. Break out the fly cutting toolz

 

the cam is a 231 239 .617 .621 @ 111+4 on LSL lobes. I really dont wana flycut the pistons

 

The recommended clearances are 080/.100 for the intake/exhaust. You seem to be quite a bit below that. If you were around .070/.090, you could prob just run a bit thicker gasket and be fine, but I doubt the clearances you measured (if accurate via the clay method) are safe gaps.

 

was re checking everything last night and actually swapped stock pushrods in and the clearanc was 63 thousadnths and 65 thousandths. Measured the 7.425 pushrods i had and they measured 7.445. Im thinking the extra lil 20 thousandths longer pushrod is whats throwing it off so bad.

 

If the pushrod length makes a difference in the measurement, you are not measuring correctly. Exactly how are you doing this? Do you have solid lifters? Based on what you have found, my guess is all your numbers are inaccurate.