I know this should go in the FI forum, but no one has any answers there.

I have a Greddy TT setup and road race my car. My crankcase deosn't have the necessary capacity to vent built up pressure. My turbo oil return lines are pressurizing and forcing alot of oil past the seals into the intercooler fowling my MAF sensor and casuing the couplers to blow off. Has anyone found an answer to relieving the pressure? A vacuum system maybe? Anything? I'm desperate.

 

Beyond my expertise, but have you talked to Sharif or maybe the owner of the Double Down TA car?


Both of them come to mind when thinking of high HP TA track cars.

 

I would try Mike-

 

catch can? but really, i have no idea!

 

Pressure into the crankcase can come from these places:

Rings
Valve guides
PCV/Crankcase vent systems

Are all of these OK on your car?

 

Use a catch can that vent's to atmosphere?

 

i was recently told by a race car shop owner that BOTH banks need to be ventilated in racing conditions, not just one. Not sure if this is true on FI, but seems to make sense. Just vent both sides and use a catch can.

 

I will answer for Jet, i was with him last weekend-the car has a catch can
system that vents into the atmosphere-did not help-car only gets about
4-5 laps of hard driving on the race track then problems occur.

 

i was gonna insert the crackcase vent mod until i saw that jet wrote that lol. so your getting blowby even though both sides are vented? please elaborate.

 

in addition to what i wrote above... i was thinking about this after I went back to work today. I have seen a lot of Cobra guys at the track with superchargers having a ton of blow by issues as well. A lot of them end up porting BOTH banks AND they will add a TON of length to the hose that leads to the catch can. Literally it will be coiled up several times before reaching the can. It may not be the prettiest way to handle the problem, but it gives the system that much more volume.

Has anyone ran a catch can for each bank? Not really weight efficiant, however.

 

I have been following your problems in the FI forum mate.

If you were to get inlets cut into the suction side of the turbo inlets behinde the air filters and run this to the outlet of you catch can then when your car comes on boost you would have equal amount of vac pulling though you catch can???

 

Correct. Thats what I'm going to try. I figure that vac would increase at about the same rate as boost increases. I'm porting my intake tube about 3" in front of and pointing towards the turbo inlet. Then routing that hose with check valve to the catch can then to the stock pcv location. The vac line to the intake manifold would be blocked off. Worse case is that it would act like an open vent system. Best results is that this setup creates vac as desired. Either way the crank case is no longer being pressurized by boost.

 

I found where my crankcase pressure was comming from. I had two cylinders with bad rings. Cylinder #2 was 14% leakdown, and #3 was 18%. That was causing the crankcase to pressurize and pressurize the turbo oil return lines and causing the turbo oil seals to leak something fierce. Gonna have to get the rings replaced.

 

reason #583721945 that I steer away from FI. I want the power WITH stability.

 

So why did you get a Z? Where's the power?

 

unfortunately poor ring sealing is a fact of life when you road race a car. Doesn't matter if its FI or NA, they are all candidates for it unfortunately

 

the Z has decent power and great handling/braking in even the most basic form. That was the original reason I bought one. Shortly there after I moved on to a non-production race car with a chevy power plant.

don't get me wrong, however, I would kill to be TT'd. I have driven a monster of a Z and loved every second. I also understand the risk, which is why i stuck with NA.

Yes rings are definately always going to be an issue with racing along with A LOT of other componets. But why speed up the process???

just my.02

 

So glad u found the problem...but it sucks that the motor must come apart to repair.

 

Ya I've been kinda following your threads, sucks that this is the cause..

 

my engine did the same thing when i had my ati procharger on it. i had oil squirting out the sparkplug socket!