hey, friend of mine has a stock 95 t/a LT1 with an sts rearmount turbo on it...only mods are

sts @ 4psi
42lb injectors
dynotuned

prob is he is getting blowby out of his oil fill cap(oil return for turbo), and out of the small breather on the pass side VC(where the pcv was previously).

One person said it is a ring, but i cant see how he'd waste a ring on a stock lt1 w/ 78k orig miles that is all stock...esp with 3-4psi, and being tuned with 42lb injectors. no misfiring, no smoke out the tailpipe, etc.

I think it is something pcv related, i did a search and came up with a bunch of people having sts pcv problems. under boost it shoots oil out of the oil fill/return cap because it isnt sealed correctly(was like that when he got the kit). how can we go about testing the pcv system? and is there anyway a mis-adjusted valve could cause the combustion gases coming out of the breather/oil cap? (his dads idea) thanks for all the help
James

 

Have him try a valve cover breather...I had a breather on the car before I switched to a catch can, but that will relieve some crank case pressure...only way to find out if its a ring it is to do a leak down/ compression test...

 

did he cap off the PCV port on the throttle body like its supposed to be? if not he might be putting pressure in this crank case. we put my old sts kit on my buddys LS1 formula and i told him to cap off the pcv on his throttle body and he didnt... he replaced valve cover gaskets a week later and then plugged off the throttle body..

 

hey thanks for the replies guys.. he does have the pcv port on the TB capped off..i think we are going to try a compression test on it just to make sure it isnt anything internal before going any further though

 

hummmm might just need a better evac system.

 

....Or could be cracked ringlands. Hope not, but that would produce some good blowby. A compression test would give you a hint for sure.

Ken R.

 

would cracked ringlands produce any smoke out of the rear of the car? b/c there is none at all..the only smoke is from the valvecover
thanks

 

Not much from my own experinece. I don't remember seeing any when i cracked 2 of my pistons. Multiple cracks on the 2nd land on #2 and #4. Never saw smoke out the tail pipe, but it was puffin' like a big dog out the VC breather. I noticed it when it started puffing out my hood scoop. Compression test had those 2 cylinders at around 60psi. Not saying thats your issue, but you might keep it in mind as a "something to check" item. Even on low boost, a little detonation at the wrong time and under the right conditions can cause issues.

Ken R.