2011 CTS-V SC w/ twin turbo MAF issue

[DVR IMP]

If I increase the MAF over 400g/s it will fall off on power big time, 50- 100rwhp. If I keep MAF @ 399g/s or under it pulls fine on the dyno.

Any Hz I command the 400 g/s at or higher is when it will fall off at wherever RPM it meets. I've had it hit at 3600rpm and up to 5300 rpm, but it runs too lean at the higher rpms. I limited it @ 399 and made huge increase in commanded pe and the mixture is good just not pulling the same power as I would like due to this. Any suggestions or similar situations I can be directed to?

Thanks,
Jason

[Cody@LoveFab]

Sounds to me like a trim is cutting in somewhere. Wish I could help.

Can you go SD/MAFless on the car? G/sec goes out the window then.

Offering suggestions...

[DVR IMP]

I did SD and had no issue. I'm just not sure if anything else would be affected - poss. TCS - if I stay SD

[Cody@LoveFab]

Ah, gotcha.

I'm pretty sure a G8 GXP I built and tuned still retained full function with SD. However, two years is a big leap for ecu/vehicle technology.

Have you checked for TCS function? Or are just worried about losing features altogether?

[DVR IMP]

I would like for TCS to be functional, but I have not test drove in SD. The builder of the turbo kit is taking the car back for more R&D to find out why the boost is falling from 15psi @ 3000rpm down to 7psi @6000rpm

[Cody@LoveFab]

TCS does still work on the GXP, I just checked the log.

Tell Turbo guy to move wastegate pressure source to furthest possible point in the chain; ie, don't pull boost from the compressor housings.

Is the SC still active?

[DVR IMP]

The factory SC is still there. They are leaning toward the intercooler being restrictive. I'll ask them where the wastegates are referencing from.

Thanks