vettezilla

iTrader: (1)

I have a 94 6 speed Corvette with a remote mount turbo setup with 10 lbs of boost and i am noticing that when I come off boost I am getting a little bit of blow by and it seems like some oil is coming out of the dipstick. I have a stock PCV valve and i have tried a one way check valve however the check valve just seemed to make things worse. What should I do to fix this?

guppymech

iTrader: (7)

Get some valve covers with breathers to let the Excessive crankcase pressure out. Are you using the stock short block? They aren't known for living under boost. You might want to do a cylinder leak down test to see how bad things are.

vettezilla

iTrader: (1)

Stock block stock internals... would a catch can help if the leak down test checks out

ahritchie

iTrader: (1)

Wow....that's a lot of boost for a stock LT1! I assume it's got a huge intercooler?

vettezilla

iTrader: (1)

No intercooler the turbo is remote mounted so the distance of the charge pipe sort of acts like an intercooler... I do plan on a meth kit in the very near future I just need this bug ironed out and i need a new scavenge pump as well

Kevin Blown 95 TA

If you remove your oil fill cap and see much smoke puffing out, it might indicate a more serious mechanical problem. Do hope it's not this, but investigate the cause of the blowby and see if you got any cylinders not making cranking or low rpm compression.

You can do a simple cranking test with the coil wire grounded and see if it is even or uneven. Uneven indicates low compression in one or more cylinder. Then do the leakdown tests if you can access the spark plug holes.



On the last run ever with my stock engine, my car still went 12.4 with a blown head gasket and these pistons. So they will still make power with the ring lands cracked.

vettezilla

iTrader: (1)

Stupid question. ... wouldn't it smoke out of the exhaust if it had a broken ring landing all the time though

Kevin Blown 95 TA

Depends on the severity of the damage to the cylinder and piston, of course. The old standby for pistons going out back when we were all first supercharging our stock engines was to check for smoke huffing out of the oil fill hole. And damn near everybody with a blower on a stock LT1 engine eventually went through this sooner or later.

Did you do the cranking test that I suggested?

Blackbirdws6

iTrader: (7)

You need more crank evac but as mentioned, you may have a mechanical issue. The pressure needs somewhere to go and since you have a closed system, it will head for the dipstick or out of the engine seals. I run a MM pcv can with one breather on the VC. No issues.

Regarding your comment on the length of pipe acting as an intercooler, I don't agree. With 10lbs of boost, you need to cool the intake charge. Def get an intercooler and/or meth. You are on borrowed time with a stock shortblock.

vettezilla

iTrader: (1)

What is a MM PCV can and do you have any pictures of your setup?

Blackbirdws6

iTrader: (7)

MightMouse catch can. PCV valve is removed from intake, tube goes to dirty side of can. From the can with the PCV/check valve, a line runs to the port below the throttle body. Once valve cover has an open breather, other is closed.

I don't have a pic handle but will take one when I am back home.