034 HF Manifold=Boost Spikes?

**HIERLEVELZ** · 11-19-2008 10:58 PM

So i upgraded to the 034 HF mani and my MBC was previously set to 15psi and now im seeing boost in excess of 20psi which is not where I want to be. Now I can simply turn the boost down but my question is would the extra flow provided by the 034 Mani create the increase in boost? My guess would be no because the MBC is mechanical in nature and the spring rate is fixed so the opening of the wastegate is a function of where the MBC is set (spring rate) and not the exhaust flow. Correct me if I'm wrong. Hope what i wrote made sense.

**HIERLEVELZ** · 11-20-2008 11:17 AM

Noone or am i just not popular enough? :(

**AudiA4_20T** · 11-20-2008 11:22 AM

just turn the boost down

**HIERLEVELZ** · 11-20-2008 03:28 PM

Yes i know i have to turn the boost down as I stated above captain obvious. Im trying to understand why the boost increased in the first place.

**A4SoftWalker** · 11-21-2008 02:11 PM

Originally Posted by HIERLEVELZ

So i upgraded to the 034 HF mani... would the extra flow provided by the 034 Mani create the increase in boost?

I also have this log manifold waiting to go in & my research showed according to those that ran b4 & after dynos:

1) A smoothing of the boost spike
2) Increase of area under the hp/tq curves
3) Modest single to low double digit incr in hp/tq

Is it possible something like ur wastegate/small hoses got tweaked during the install? When I installed my TIP I had a kinked wastegate hose do the opposite and "prevent" me from building boost.

**HIERLEVELZ** · 11-21-2008 04:46 PM

I had a look under the hood today and noticed that the adapter flange on the turbo inlet was missing the two socket head cap screws, so the TIP was basically haning off the turbo a few millimeters. The car threw a cell and was running rough so im guessing that had alot to do with it and possibly the boost spikes. But I will look over the hose that goes to my wastegate.

**HIERLEVELZ** · 11-23-2008 03:53 AM

Ok turns out that my MBC was bad. I ruled out wastegate creep by disconnecting the MBC and connecting the vaccum lines together. The turbo produced a steady 10 psi which meant that the wastegate was operating properly. I bought a new turbosmart mbc and the psi is holding at 20psi just have to tweek it a bit more and im set.

**F16HTON** · 11-23-2008 07:19 AM

034 does not make a hi-flow manifold...

You have an ATP manifold sold by 034

**HIERLEVELZ** · 11-23-2008 12:19 PM

Originally Posted by 400HPA4

034 does not make a hi-flow manifold...

You have an ATP manifold sold by 034

Oh really thats not what I was told and I think we've been down this road many times. Lets see if Issam willl chime in on this one.

**034Motorsport** · 11-24-2008 03:17 PM

I think this one has been beat to death, but ATP has a manifold and we have our own cast manifold, they are far from identical, both serve the same applications.

We have no reason to lie about this, we do sell many ATP products which we're happy to disclose that they are. If we were lying, it would be a very easy lie to uncover, we have no reason to lie about this.

If anyone has any questions, please feel free to let me know.

Thanks,