Blowby questions

[bfarroo]

I have some weird blow by issues with the shadow. I took it to the first autocross of the season today and noticed some oil leaking out of the airbox after the first heat. Pulled it into the pit area and removed the airbox and there was a bunch of oil in the bottom of the airbox from the PCV system. I cleaned it all up, put a small bunched up piece of paper towel in the bottom of the airbox where the PCV tube enters and went back out on the track. Made the first lap and pulled the airbox and it's dry. Make the second round put the airbox and it's dry again. Make a third pass and there's a puddle in the bottom of the box again. All runs were run relatively close to the same. When I got home I noticed the cam cap had also popped out. Specs on the car/motor. 88 Shadow w/ 88 Daytona TII motor with factory intercooler, Mitsu turbo, +40's 3bar. running 15-17PSI. Engine was rebuilt 4-5 years ago and has a few thousand miles on it max. It has seen only autocross / Ice Racing / Ice Cross so they've been all hard miles. I'm going to pop a new cam cap on tomorrow and run a compression test. I may add a exhaust evac system and catch can if I have time before the next race if everything checked out good.

LMK what you think. I'll try and post up tomorrow as to what the compression #'s are.

[turbovanman²]

Is your PCV setup stock or ?

What PCV are you using? The stockers aren't any good anymore and leak, get a Supra turbo unit.

Do a leakdown test, more accurate than a compression test.

[bfarroo]

PCV is a stock setup with a stock valve. What is the typical issues with the stock valve. What year supra should I be looking for a valve from. I don't have a leakdown tester but may look into purchasing one.

---------- Post added at 09:12 PM ---------- Previous post was at 09:06 PM ----------

Will a cheap harbor freight leakdown tester work ok. Looks like they have one on their site for a little lest than 40 bucks or should I be checking a few tool stores.

[turbovanman²]

Compression test won't give you the full picture, you can still have bad rings with good compression.

Redo the pcv system using a catch can, that will help big time.

I can't find the part number, I"ll dig it up tomorrow.

[tryingbe]

Go to a TOYOTA dealer, and ask for P/N 12204-46020.

DO NOT BUY aftermarket junk. Use the dealer part only.


Cast n/a valve cover also works better than the turbo valve cover.

[csxtra]

Cast n/a valve cover also works better than the turbo valve cover.

The baffle curtain/two hose outlet setup on the TBI valve cover does work much better for venting the crankcase.

But for autocrossing/road courses/hard cornering, the baffle curtain doesn't prevent oil pooled in the head from getting into the PCV hoses. If you run that valve cover and plumb the hoses into either the intake or the exhaust (using venturi valves) without a BIG catch can, you'll get a LOT of oil smoke when cornering.

[DodgeZ]

PCV is a stock setup with a stock valve. What is the typical issues with the stock valve. What year supra should I be looking for a valve from. I don't have a leakdown tester but may look into purchasing one.

---------- Post added at 09:12 PM ---------- Previous post was at 09:06 PM ----------

Will a cheap harbor freight leakdown tester work ok. Looks like they have one on their site for a little lest than 40 bucks or should I be checking a few tool stores.

The stock aftermarket valves leak, even the new OEM ones. Take the valve and pressure test it with an air compressor set a 20psi. If you get a supra valve you HAVE to get one from the dealer.

[DodgeZdad]

If the system is similar to the Srt-4, even if the PVC is good, any blow-by will be vented to the airbox while in BOOST.

[bfarroo]

A catch can is definitely on my list. I think I'm going to order a evac valve setup and get rid of the plumbing into the intake and go from the VC to the catch can to the evac. Also I've heard it's better to run the evac on the bottom of the block instead of the valve cover, is that worth doing?

[bfarroo]

Picked up a leakdown tester. Was at 13% on 1, 5% on 2, 8% on 3 and 6 % on 4. Compression was 135 on 1, 130 on 2, 132 on 3, 135 on 4. Engine seems healthy so I'm going to work on the PCV system. and hopefully that takes care of it.

[turbovanman²]

#1 is a bit higher than the rest, it could get worse at the engine heats up, hence why it takes 3 runs to fill it up with oil. Keep an eye on that cylinder.

[DodgeZ]

#1 is a bit higher than the rest, it could get worse at the engine heats up, hence why it takes 3 runs to fill it up with oil. Keep an eye on that cylinder.

it only took one run to fill it up

[turbovanman²]

it only took one run to fill it up

He said third pass,

[bfarroo]

Everything was fine until the third run. I don't know if I would have been pushing a little harder or what but it's weird that it went from nothing to a good sized puddle. I'm going to get the PCV sorted with a catch can and see how things go in two weeks.

[DodgeZ]

He said third pass,

He said he had two runs and there was NO oil. Then he had run, just one, and it filled it up.

[bfarroo]

I'm going to try and pick up one of these and give it a whirl.

http://www.jegs.com/i/JEGS+Performan...52210/10002/-1

From there I think I'm going to try finding a TBI valve cover. Anyone know where to find a cast TBI valve cover or what cars they came on. I don't look at TBI cars much at the yard but can't remember seeing a cast one before.

[turbovanman²]

He said he had two runs and there was NO oil. Then he had run, just one, and it filled it up.

So drum roll, that would be the THIRD pass.

I'm going to try and pick up one of these and give it a whirl.

http://www.jegs.com/i/JEGS+Performan...52210/10002/-1

From there I think I'm going to try finding a TBI valve cover. Anyone know where to find a cast TBI valve cover or what cars they came on. I don't look at TBI cars much at the yard but can't remember seeing a cast one before.

I have one, $20 plus shipping.

[bfarroo]

I'm going to get one for each of my cars since I don't have any PCV on the daytona so I can kill two birds with one stone. Hopefully this takes care of it.

[DodgeZ]

#1 is a bit higher than the rest, it could get worse at the engine heats up, hence why it takes 3 runs to fill it up with oil. Keep an eye on that cylinder.

it only took one run to fill it up

He said he had two runs and there was NO oil. Then he had run, just one, and it filled it up.

So drum roll, that would be the THIRD pass.

Not sure what THIRD pass has to do with anything. You said it takes 3 runs, and it didn't.

It must be fun to live in Simonland...

[Ondonti]

How did plug #1 look compared to the others?