I just installed my new boost gauge. I have a .5 bar Tial wastegate. When I get into boost it goes to 7psi and stops but slowly creeps from 7 to 9. It should not be the gauge or the wastegate and I have a 3" Thermal with a 3" high flow cat. My DP is 2.5" but for my application that should be fine. What else could be causing this creep? Thanks!

 

The manifold and the 2.5inch dp to 3inch cat and exhaust... When I install my 3inch Thermal I boost spike like crazy with my drag manifold, 2.5dp and 2.5 to 3inch testpipe!

 

Wouldnt the 3" high flow and 3" Thermal help reduce back pressure thus eliminating creep? Or at least reducing it to an un-noticable amount?

 

what kind of manifold? your wastegate opening on the manifold might need to be ported. that stopped my boost creep. could also have exhaust leak from a cracked manifold. check it out

 

i get boost creep too. just learn how to adjust the boost controller and adjust it accordingly

 

You can't adjust boost creep out with a boost controller.

Decreasing backpressure makes boost creep WORSE. The higher flow your exhaust is, the happier the exhaust will be going through the turbine, and the more creep you will get.

You need more wastegate flow, either with a better wastegate, a larger wastegate, a better mounting idea, or a better way to dump it back into the exhaust.

 

Well, I have a Tial 38MM I cant see going to a 40MM for a under 300HP application. It is an open air dumptube that is the same size as the wastegate exit so there is no restriction there. So what else? I really appreciate all the ideas!

 

You could have minor cracks in the o2 housing(if you have one) or on the manifold do some minor porting and it should fix it plus 2.5" exhaust is plenty

 

I disagree about the 2.5" being plenty. The bigger the exhaust the better for a turbo application. I have no cracks in the o2 housing its brand new. How can I check if the manifold is cracked w/o taking it off the car?

 

Are you using a drag manifold?

Also, I fixed my boost creep a few days ago. The fitting on my wastegate was way too small.

 

wastegate placement on manifold plays a big role..

 

I was wondering if you were able to fix this problem?

I'm running into the same problem running a drag manifold, .5 bar Tial wastegate, 2.5" dp, and 3" piping and exhaust. It creeps from 7 psi to 9psi. Thanks.

 

No, I never really fixed it. It creeps to about 8 or 8.5 but it never goes over 9 so I dont care. I imagine a lovefab manifold would help but I am going broke quick!

 

Sooo maybe I missed it, but what kind of manifold were you using again?

 

Thanks.

Yeah, I don't have the funds for a new manifold yet either so I was hoping there would be another, cheaper solution. Oh well.

 

I am running a spark racing manifold. Hopefully it will last me till I can afford a lovefab or full race.

 

Ironically, the larger wastegates also eliminate creep. Though 35mm is large enough for both applications, other than a boost controller, only a LARGER wastegate can help eliminate it..

Ask Tial. I know.. I know, the logic is strange, but it's true.

 

So I have a 38mm that should be plenty! A 40mm would be overkill right? Will using my turbo XS boost controller help at all?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheShodan &raquo;</TD></TR><TR><TD CLASS="quote">Ironically, the larger wastegates also eliminate creep. Though 35mm is large enough for both applications, other than a boost controller, only a LARGER wastegate can help eliminate it..

Ask Tial. I know.. I know, the logic is strange, but it's true.</TD></TR></TABLE>

thats not entirely true.

the wastegate placement on some manifolds are so shitty...

 

I have an EVC I. How will adding the boost controller prevent the boost from creeping?

Thanks.

 

what you can do to stop creep on that mani fold is weld a pipe crossover from another cylinder they are not really that great to start with. Everyone has creep on it. But that will fix it and be over with it

 

everyone heres been tryin to help and most have asked you wat manifold you were running, although from what i've read , you took your time before you posted what manifold. all n all, i think your problems lies with your manifold. a common problem with tubular meng style mani's. could've saved everyone a lot of time by just saying you had one from the get go.

also, i have one of the these meng style manifolds.......no boost creep here.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by RedTegLS &raquo;</TD></TR><TR><TD CLASS="quote">I am running a spark racing manifold. </TD></TR></TABLE>

I think that your problem. Like Mase said <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mase &raquo;</TD></TR><TR><TD CLASS="quote">the wastegate placement on some manifolds are so shitty...</TD></TR></TABLE>

 

Modified by RedTegLS at 8:17 AM 2/4/2004

 

If your only experiencing a small amount of creep.....1-2 psi max.....I know what fixes the problem! A manual boost controller!!!! I just installed my TurboXS MBS and turned it up 2 full turns and took it out. 10psi dead nuts everytime! It used to go to 5 then 7 then 8 then creep a little past that. Now it goes from about 2 and smacks right to 10! Bam! Loving it!