Could this be a question the wisemen can;'t answer?

[P8ntBalla]

ok, well i got my ported/clipped 16g and ported exhaust manifold on, and my boost creeps like a mother####er. there is no exhaust restriction behind the wastegate, and i have gone through all the vacuum hoses and intercooler pipes, and just about everything else i could think of. i even swapped my hallman mbc out for the kind that is milled out of a block of alluminum and it still does it. the turbo is brand new, so i dont think the wastegate could be bad.

me, as well as the people at my shop, are completely confused; that is why i have turned to the wisemen. can you think of anything else that i should look at or replace?

 

[90GSX]

Is the O2 housing stock? Porting the WG passage in the O2 housing should reduce boost creep.

Have you tested your WG actuator with a vacuum/pump tester? Be sure it's actuating correctly.

Good luck,

 

[candela]

Try porting out the wastegate passage and even getting a larger flapper for it. When I had a 16g, i used the 34mm flapper and had a lot of porting done nd I never even had .5 psi of boost creep its whole life =)
If you ahve nice porting done to it, and then you have a free flowing exhaust (no 3" to 2.5") then you should be good to go


Austin

 

[Tevenor]

Give us more details. What o2 housing? What exhaust? Cat or no cat? Size?

 

[P8ntBalla]

its a 3" mandrel turbo back(it is an 02 elim dp, but its cut and flanged like a normal downpipe would be for an easier install, the 02 housing part is ported extensively). the wg passage is also ported extensively, however i dont have the bigger flapper. no cat (i love fla!).

how do i make a tester for the wg? or do i just use a normal intake leak tester?

 

[90GSX]

Originally posted by P8ntBalla
its a 3" mandrel turbo back(it is an 02 elim dp, but its cut and flanged like a normal downpipe would be for an easier install, the 02 housing part is ported extensively). the wg passage is also ported extensively, however i dont have the bigger flapper. no cat (i love fla!).

how do i make a tester for the wg? or do i just use a normal intake leak tester?

If it's an O2 eliminator DP, then why is it ported extensively? The tubular O2 housings are not ported, they're large diameter tubing that doesn't require port work.

To test the WG actuator you use a vaccum hand pump tester, which I presume is available at most autoparts stores. Connect the tester to the WG actuator and pressureize it by pumping, watch the gauge and see what psi the actuator begins to open the WG.

 

[P8ntBalla]

when we took the 02 housing part off it had a black ring where the exhaust was smacking right into it, so he used that as a template to port it out.

 

[nine5raptor]

then you have a ported 02 housing. an 02 eliminator downpipe bolts directly to the turbo and goes back to the cat (short) or catback (long)

 

[P8ntBalla]

k, but i still have boost creep!!!!!!

 

[turbotalon92]

What does it creep from/to?

How is your boost controller hooked up?

Turbo bought new or used?

 

[marshall]

so get a wastegate that flows more, it's pretty damn simple...whether it means going external or porting the internal w/g hole. how many times has this been discussed in the past?...

 

[P8ntBalla]

Originally posted by marshall
so get a wastegate that flows more, it's pretty damn simple...whether it means going external or porting the internal w/g hole. how many times has this been discussed in the past?...

wg hole is ported.

creeps from 10(where i guess it would be set if it wasnt creeping) to 20(where i let off the gas for fear of my hg blowing).

the boost source is the line going from the bov to the intake mani plenum, then to the wg.

turbos brand spankin new.

 

[L2RTSiAWD]

Well than yiou either need a bigger internal wastegate or your going external.

 

[P8ntBalla]

thats all i could think of but how could a wastegate made for a specific turbo be too small for it?

 

[BatmanGSX]

Originally posted by turbotalon92
What does it creep from/to?

What I want to know is why nobody asked this before you and also why it hasn't been answered.

 

[P8ntBalla]

Originally posted by P8ntBalla




creeps from 10(where i guess it would be set if it wasnt creeping) to 20(where i let off the gas for fear of my hg blowing).

 

[blackawdturbo]

Originally posted by P8ntBalla


wg hole is ported.

creeps from 10(where i guess it would be set if it wasnt creeping) to 20(where i let off the gas for fear of my hg blowing).

the boost source is the line going from the bov to the intake mani plenum, then to the wg.

turbos brand spankin new.

Personally I think 10 psi is way to low a boost level to maintain with this turbo, especially with a stock internal flapper. That is alot of exhaust gas that needs to be bypassed to maintain that low boost. My 16g creeps from 15 to 20 psi and that is with a highly ported o2 housing and 34mm flapper, and cold weather aggrivates this problem more. Remember a creeping car means you are making good power, you just need to control it better . There may not be much you can do without enlarging the flapper or going external.

 

[NosLaser]

Ummm...it's creeping up to 20psi..and you are complaining because...??

That is the boost you SHOULD be running with a 16g. Why are you trying to run 10 psi in the first place? If you wanted to run 10 psi, why did you even upgrade your turbo?

Regards,

 

[Boosthungry]

Originally posted by blackawdturbo



Personally I think 10 psi is way to low a boost level to maintain with this turbo, especially with a stock internal flapper. That is alot of exhaust gas that needs to be bypassed to maintain that low boost. My 16g creeps from 15 to 20 psi and that is with a highly ported o2 housing and 34mm flapper, and cold weather aggrivates this problem more. Remember a creeping car means you are making good power, you just need to control it better . There may not be much you can do without enlarging the flapper or going external.

Yep good call, my thoughts too.

 

[P8ntBalla]

i dont want to run 10 psi. ok let me try to explain this better(i suck at saying stuff on the internet).

i want to run about 15psi because im still on the stock injectors(190 pump, but stock control and injectors). i have the screw on the mbc so far out that it isnt even touchingthe spring. that makes it boost right up to 10, then creep till i let off. if i make it any tighter, the second i stand on it it will boost to 20-25 psi(i dont know if it will go further, i dont want to risk blowing my hg).

could the smaller flapper be causing creep? i would imagine that it would restrict less flow if anything.

i dont see how it could be possible that i would need to go to an external wastegate with such a mild setup.

im not trying to prove anyone wrong or anything, dont take anything personal, i just dont quite get whats going on.

 

[BatmanGSX]

What's going on is you should be running 20psi.

Yes, you can run 20psi on pump gas with stock injectors.

Boost creep isn't always bad, it just means you have a good running car. Your car wants you to run 20psi. It's telling you something.

 

[candela]

that is quite a creep you haev going on... have you ever stayed into the gas to see how high it goes? Maybe you have you boost controller hooked up wrong, or maybe it isn't working properly. You are right, you should be able to run (dont know about 10spi...thats less than stock) low boost with that setup without creeping to much. But its true what everyone else said, why not turn that sh!t up and enjoy your new turbo Make sure there are no weird restrictions in your setup like gaskets being way off or your wastegate not opening all the way... Id once over everything than maybe consider cranking it and/or porting out the w/g more

 

[P8ntBalla]

im gonna stay on the gas today. ive seen it up at 25 psi. ive got the mbc setup with the line from the bov to the plenum as the boost source. im gonna try sticking it in backwards to see if it will keep me at stock boost just for shits and giggles.

it doesnt seem to like 20psi though, when i get to about 18-19 it starts to miss, but im pretty sure thats the stock heat plugs, im gonna swap in some bpr7's.

 

[marshall]

instead of switching the mbc around, just take it out, run a vacuum line from your boost source directly to the w/g actuator. if it still creeps then you know it is purely a w/g problem.

marshall

 

[P8ntBalla]

good idea, going to do that today.