Need Help Finding the Boost Problem.

[poneypower89]

Ok, so a day ago I switched the pulley on my vortech for a smaller one. I went from a 3.33 to a 3.12. The stock pulley was supposed to give 5-6 psi.

Anyways, the boost gauge is barely just tapping 5 psi..

The belt is brand new. Goodyear Gator back. Its as tight as piano string.

The car is otherwise stock save for full exhaust and gears... So, no *head* effeciency should be making my boost low.

The only two things I can think of at the moment are a weak by-pass valve.. (its the cheap plastic bosch)

OR, the boost gauge might be malfunctioning. (it does have a very small kink on the hose, but I was able to blow thrown myself just fine... )

The air filter IS a little dirty, but I doubt that would keep me at 5psi.

Anyone have any idea on how to go about getting my boost up to par? How can I test the by-pass valve? How would I know its bad?

the vaccum reads around 18-20 at idle and go straight to zero if I tap the gas... so the gauge SEEMS to be working.

I dunno, help me diagnose this please.

 

[poneypower89]

no body has an idea uh?

 

[poneypower89]

wtf? no one? ok.. fine.. im just ordering a new BOV/By-pass then and seeing what happens

 

[71swing]

Take off the bypass see what happens

Bypass valve is not need really till you get to 8-9psi

I ran a SC-trim on my 88lx and had no problem get 5psi above 3000rpms
I never ran a bypass valve. Those small of kits don't even come with them ,you must have purchased it seperate.

 

[poneypower89]

yea, I bought the aluminum discharge tube.. and it came with the bypass valve...

I HATE and i repeat HATE that jank plastic tube soley because.. well it looks jank

Anyways, would put the plastic tube back one just to see if the bypass was the problem.. but its currently 2 hours away since I moved to a different city 3 weeks ago and left most of my stuff with my father cuz the stang can only haul so much......




So, do u sespect the bypass valve? or would there be any other reason?

 

[71swing]

You never said what you were getting for boost, just that you cant get 5psi.

The smaller pulley should get you a solid 6psi maybe 7psi. Think you need a 2.75 to get to the 8-9psi.

Have gone over all the factor vacum hoses? maybe one go blown off? Or may just be alittle worn and cant see it? It hard to inspect the vac lines in the rear of the intake sometimes.

The supercharger put out enough boost that if it were alittle leak it may just lower the boost but still be enough to supply the engine at idle to not notice anthing wrong.

PCV vlave could also be worn have you ever replaced it?

If they all check out I would point to the bypass.

 

[Acid7711]

You never said what you were getting for boost, just that you cant get 5psi.

the boost gauge is barely just tapping 5 psi..

Aside from that, I don't know if it's your problem, but I would make sure that all vac/boost lines have zipties tight around them at both ends. That would at least help eliminate one of them possibly leaking boost to the atmosphere.

 

[71swing]

Have gone over all the factor vacum hoses? maybe one go blown off? Or may just be alittle worn and cant see it? It hard to inspect the vac lines in the rear of the intake sometimes. 71Swing

I don't know if it's your problem, but I would make sure that all vac/boost lines have zipties tight around them at both ends. Acid7711

Aside from that

 

[Acid7711]

Aside from that

At least I read what he wrote. What I wrote is no where the same as what you did. At the very least I offered a solution to counter the possible problem.

Perhaps if you sit back and read what I wrote and compare it to what you did, you'll soon realize your answer was pretty much useless, seeing how yours wouldn't stop boost from leaking, if it was. What you wrote would only make sense if one of the tubes was completely blown off, and that's usually not the case.....

So I ask again, how is a visual check under the hood outside of boost going to reveal vac lines that are still on but leaking air under high boost? Keep laughing.