71 chevy

iTrader: (18)

i sold my lq4 to a guy and just got word that when he bolts the heads down, the piston is contacting the head.

head are unworked 799s

has anyone seen anything like this?

badazz81z28

iTrader: (6)

Yeah, its called "piston to valve" contact. Typical when you run a long duration/high lift cam with pistons that don't have valve reliefs. Nothing you can you can do. He needs to fly-cut the pistons or run a smaller cam.

71 chevy

iTrader: (18)

sorry, I forgot to mention that he hadnt installed pushrods or rockers. It is not P2V

Im scratching my head on what it could be.

btw, thanks for the post. since I didnt post "500rwhp dyno results" I was afraid I wouldnt get any replies lol

RonSSNova

iTrader: (3)

Maybe he forgot head gaskets.......
Pistons usually out .007".......so with no gaskets, they will hit the head,
Is he mocking things up or what is he doing?

mkvamso

iTrader: (2)

^^
Thats what id put money on

RonSSNova

iTrader: (3)

Or maybe is using 5.7 head gaskets?

mkvamso

iTrader: (2)

Its still .056 or so thick
Shouldnt be anywhere close

71 chevy

iTrader: (18)

thanks for the replies guys. he did say he is using stock headgaskets.

i forgot to ask if he ordered ls1 or lq4 headgaskets lol cos if he ordered ls1 headgaskets then that would be the problem.

thanks all. i will find out today.

is there any other possible situation that could cause this? i mean, i had 862 and 317 heads on the thing and never had a problem.

RonSSNova

iTrader: (3)

If he used 5.7 gaskets and they are smaller than the bore, the piston will hit the gasket. But I've never messed with a 6.0.

JustAFooL

iTrader: (45)

I had a friend do this. It would be my guess that the piston is hitting the gasket.. Who knows though.

71 chevy

iTrader: (18)

hi, he just double checked the gaskets and they are the wrong ones. he got sent ls1 gaskets instead of lq4.

thanks all for the help

JustAFooL

iTrader: (45)

Great to hear, puts you in the clear.

7beast

iTrader: (30)

lol iam glad its an easy fix