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Intake Plenum Question - Dropping Boost - Also Good Tools To Have When Owning Skyline For $29 !


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Made mine up using a piece of metal tubing the same size as my inlet pipe. Simply welded a cap on it and fitted a tubeless tyre valve.

We have pressure tested 4 lines with it to date, 2 with known boost leak probs which we found and fixed and 2 with the owners claiming no leaks. Both of these tests revealed multiple boost leaks.

Its a very worthy excercise imo.

Nice work fineline. Where were the main boost leaks? So you attached the inlet pipe you made to the trubo inlet hose? So you are effectively pressuring up through the compressor side of turbo?

Cheers

Edited by benl1981
So Adriano, do you think wack the old gasket back in with some goo? I can't see any holes in it. Anyone got any ideas from the photos?

Use HYLOMAR spray.... it is god on metal gaskets.

Well after adding gasket goo (to intake plenum gasket) and blocking BOV I am still getting huge boost loss after 5500-6000rpm. I am just dropping my cat to see if it looks collapsed. There is no evidence of leaking at the plenum gasket now so I think that's sealed.

I will make the pressure tester and check the inlet tract.

Only other thing I can think of is weak valve springs but you wouldnt think that would change in a week!?

I guess my centre muffler could have issues.

**PROBLEM SOLVED*** modified stock snorkel not allowing enough airflow or sticking to bonnet

Edited by benl1981

Hey fineline. What about the hose that takes the blow by from the rocker cover? That is connected to the rubber intake pipe. Should you block that so you dont pressurise the top half of the engine?

Cheers

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