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I ran the autotune yesterday and am finally drivable!

Problem I have now is that oil is blowing out through the oil cap.
Im guessing i have too much pressure in the cam cover that is not able to vent out fast enough.

Am running the twin TB setup and MP45 SC, otherwise motor is stock.

How do people get around this?
Maybe a bigger vent diameter?
Would changing the pcv do anything, I'm guessing not?
Do I need a catch can?

Thanks heaps

You have blowby because your rings are a bit worn, you need 2 large hoses on the passenger side going into a good catch can.

speed wrote:Problem I have now is that oil is blowing out through the oil cap.
Im guessing i have too much pressure in the cam cover that is not able to vent out fast enough.

Can you explain this a bit better? With the cap off, you're getting a pumping pressure and small amount of oil thrown out, or a solid pulse with lots of oil coming out?

With the cap on, does it push the dipstick up? Do you get the same solid pulsing sound out of the dipstick tube?

I would be doing a leak down test. A catch can is a good idea regardless, but the concern should be tested to confirm the actual fault.

With the intake setup, I'm guessing you have kept the PCV, where have you ran the second breather?

TrackAttack wrote:

speed wrote:Problem I have now is that oil is blowing out through the oil cap.
Im guessing i have too much pressure in the cam cover that is not able to vent out fast enough.

Can you explain this a bit better? With the cap off, you're getting a pumping pressure and small amount of oil thrown out, or a solid pulse with lots of oil coming out?
With the cap on, does it push the dipstick up? Do you get the same solid pulsing sound out of the dipstick tube?
I would be doing a leak down test. A catch can is a good idea regardless, but the concern should be tested to confirm the actual fault.
With the intake setup, I'm guessing you have kept the PCV, where have you ran the second breather?

Thanks TA,
With the oil cap secured, test drove. Checked engine bay, now covered in film of oil as escaping from oil cap.
Yes I kept the pcv and ran the vent back into the intake elbow before the stock TB.

NitroDann wrote:You have blowby because your rings are a bit worn, you need 2 large hoses on the passenger side going into a good catch can.

Thanks Dann.
Any chance I could trouble you to put up a pic showing what you mean?
Would help knowing where exactly and what size

Am guessing I will need to drill and tap but the pic should confirm this.

Thanks again!

Yes I kept the pcv and ran the vent back into the intake elbow before the stock TB.

Running 2 TB's yeah? So there will be pressure into that vent yeah? As a test, you could disconnect that vent and let the engine breath atmo. Move the hose into a bottle for testing, as if it pumps out oil, you'll want to catch it. I think perhaps you're pushing positive pressure into the engine.

It's always hard on a forum to get an exact idea of what's happening, so I hope I understand you correctly. The passenger side vent needs to be away from any positive pressure i.e. any charge pipes. I would run it behind the air filter/before the intake of the supercharger, or to a catch can.

TrackAttack wrote:It's always hard on a forum to get an exact idea of what's happening, so I hope I understand you correctly. The passenger side vent needs to be away from any positive pressure i.e. any charge pipes. I would run it behind the air filter/before the intake of the supercharger, or to a catch can.

This sounds like it could be the problem & solution.

Thanks heaps guys.
Big oops on my part!

OK going to run a catch can

Would it make a difference if the "pre SC location" is plumbed between;
1. air filter and 1st TB or
2. after 1st TB and pre SC?

Just less work to plumb into location 1 ;)

Thanks again. Is great to finally be on the road again

I would have it pre TB.

Thanks so much Track Attack, Dann and Nevyn72.

Fitted a catch can on saturday and I confirm that the issue has gone away.

Still kicking my self for making the error. Thanks again