kapolani

iTrader: (6)

I got Comp 272's installed in my car and got a custom tune from Al at dynoflash the same day.

While doing the tuning Al noticed that my car doesn't seem to hold boost like other cars till redline. His MAP sensor was showing that I'd peak to 21 psi and taper to 17ish way before redline.

We did a boost leak test and found no leaks.

We swapped out my Turbosmart BOV and put a JDM Evo IX DV in and still seemed to get too much boost taper

We even swapped out my Forge MBC for another Forge MBC and still the same thing happened.

I've done several 3rd gear pulls and datalogged with my Defi BF gauge and when looking at the replay I taper to 17 psi all the time!

So, for the heck of it, I did a pull in 4th gear. What I found interesting was that with the 4th gear pull I hold boost rock solid at 20 psi all the way to redline. I actually let off at 7k rpm because in 4th you get some ludicrous speed going.

What the heck is happening?

I know there is more load in 4th so could that be the reason that I'm holding boost better in 4th gear?

Any ideas why I'm not holding boost in 3rd gear that well?

FWIW the car is rediculously fast now. The cams are great and the tune is great. I just would like to get the car performing optimally and get rid of this taper.

GoneIn420

iTrader: (8)

By the way you talk about your car being really fast and not down on power, the boost taper is perfectly normal. The boost controller should hold it a little better. but it will still taper at high rmps. Peace.