First off, the basics

05 VIII MR
Engine Mods: TBE w/ test pipe
HKS SSQV VTA

No flash, no boost controller (I'm 99% sure this is my problem)

Just finished installing my Defi BF Boost gauge yesterday afternoon. Went out with my bro in law last night (30F or so btw) for some spirited driving and hit the fuel cut on a hard 3rd gear pull. I checked my peak readings on my boost gauge and it was up at 27psi!!! EGT's didn't get that high and the car seems fine so I don't think I hurt anything.

Now, 2 questions. 1) As you see above, I don't have any kind of boost control or flash. I've read that lots of people are hitting the boost cut with the cold + TBE. A MBC and flash should solve that (cough AL you'll be hearing from me shortly). Anything else I should check out. I don't want to complicate the problem with more mods just to find out there is a problem with something I already have.

And the second question is 27psi seems really high, even for bad spike. I'm not saying it's not possible, just high. The boost gauge had been in the car for all of 3 hours when I saw the spike. Is there any simple way to calibrate the gauge and make sure it's accurate? I'm surprised the stock ecu allowed 27psi before the fuel cut kicked in.

Thanks...

 

Where did you tap in for your guage?

 

yeah 27 does seem kind of high, when it gets really cold like it is now, my boost gauge will read 23-24 psi at fuel cut (on 92-93 octane) (which i try to avoid, now i turn down the boost depending on the weather outside) its fine upto 22 psi with 93 octane gas when temps are out of the teens (no fuel cut)

 

I actually disconnected the stock MR gauge and tapped it at the FPR.

 

Check with another boost gauge to see if yours is accurate.