harmless

LS1 has about 35k on it. Only has a comp thumper cam and shorty heads with a tune. Car has never wanted to idle so that's not the problem here, just never had the time to tune it out. If i scope the motor, you can only hear the squeal through the first few valve cover bolts then it fades away to the rear. Took belt off and still made the noise ... At 2800 rpm cruising the motor makes 55-60psi, WOT is about 70 psi, and at idle about 35-40 at 900 rpm.

Link to video

https://www.youtube.com/watch?v=aRkz...ature=youtu.be
Im a as this my first ls1, all help it gladly appreciated.

Paul Bell

iTrader: (9)

Vacuum leak? Clogged cats?

Wrong section? This is the INTERNAL engine section.

harmless

its is internal..... i scoped the motor and it in fact coming from the motor. no cats... no vacuum leakes... already tried it all

Mercier

iTrader: (15)

Try taking your oil cap off. Several folks this year on these forums have had an issue where PCV vacuum was sucking air past the oil filler cap and making a squeal sound.

SethU

By "scope" do you mean a mechanics stethoscope? If so, try listening to your timing chain cover if you haven't already. Anything? Perhaps one of the cam bolts has backed out since the cam swap and is rubbing the inside of the cover.

RockinWs6

I'd pull the valve covers and look for signs of oil at all the rockers. Sounds like metal against metal from here.

Also sometimes when a lifter roller wheel fails and seizes it can sound like this.


Another thing it could be is a spun rod bearing, they can squeal just like that too. Look carefully at you engine oil for signs of silvery copper coloring or a metallic look to the oil.

You are going to have to tear into this to find it. I'd start at the rockers 1st.

SethU

This was my only other WAG. Skidding lifter.

Anthony Williams

iTrader: (3)

That is the sound of a flattened lifter roller, please see my post called LS SWAP FROM THE TOP. Replaced my LS1 with a crate LS6 due to this same issue.

harmless

Was a flat lifter.... destroyed my cam aswell. Ls7 lifters ordered and custom cam on the way. Have to wait till they come in so i can get the correct push rods.