Always be sure to check for "boost leaks", symptoms sound very similiar to one.

 

Bump because I had the same issue today

 

And you found out you were running the wrong scaling for the MAP sensor. You thought it was a 3 bar but was in fact a 2.5 bar. Re-scaled and 800rwhp/830ft lbs of tq.

 

Yes.

 

Oh dude, come on... Dyno the thing already 😁

 

LMAO, two years later......

 

Funny I'm having the same issue. I've thrown all kinds of parts and plugs at it. I'm dumbfounded.

 

Two years later and it's actually fixed. Took the heads in and had the spring pressures measured. Needed to have the springs shimmed ... Now is pulls fine on the dyno. HP and TQ track linearly until TQ passes HP around 5500. The car is running better than ever!