Help with first ls1 build
Thread Starter
Teching In
Joined: Mar 2019
Posts: 2
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Help with first ls1 build 
I have a 2001 Z28 with ls1 5.7l with 241 heads 118k miles cylinder 7 has lost of compression its 50-70psi. There's oil getting in the cylinder but I have no oil bypass from my crank case like I have no pressure even I take the oil cap off. I checked cam vavles arm to be moving fine can barely tell the miss in cylinder 7. but I have air bubbles in my rad when I rev it. I was going to tear the motor down and replace all my pistons and rings. But I don't know what I should replace them with I was just going to stick with stock or go with foraged pistons stock size if I can. But I'm lost on finding what I need. Any help would be appreciated
Thread Starter
Teching In
Joined: Mar 2019
Posts: 2
Likes: 0
Headgasket It's sitting in my driving it I thought it could be va head gasket too but I read on here about how cylinder 7 has problems and how the aluminum heads warp so I thought about just tearing it down and doing a complete rebuild. I just don't know what steps I got to take.
There are some pistons out there you can use with your stock connecting rods but if it where me I'd be looking for a decent set of forged rods and pistons. You can reuse the crankshaft but you will need to send in the new rods, pistons and crank to a engine machine shop be balanced before assembly. Depending on what you plan to do with the engine will dictate what direction to go with your piston selection.
