engine cutting out, help :(

[mxracer27]

hope getting my car tuned fixes this. My car doesn't redline until 6K rpm's, and it pulls really hard until that, building around 11-12psi of boost. Sometimes it pulls hard to 6K through all of the gears, but sometimes in 2-4th gear I will reach around 5K rpm's and the engine just loses its power, and the boost gauge drops from 11psi down into the vacuum section, or 0 on the boost gauge. The engine isn't pinging at all like its detonating. I have no clue what is causing it, the a/f ratio gauge is in full green, and when it does this, the a/f ratio gauge still stays in the green, telling me the fuel isn't cutting out. I put my computer chip on +4% fuel and it seemed to cut out even earlier around like 4800rpm's. Any ideas??

[Matt'sRoush]

Get it tuned. I wouldn't trust a regular A/F meter. Get a wide band.
What else have you done besides the blower? (Sorry, too many V6's to keep straight lately.)

Thinking out loud : What I'm wondering is the redline being at 6K. Is it redlining and peaking out or is it hitting the rev limiter? Sounds more like a rev limiter. The rev limiter in our cars seems to vary with speed and gear. I know that sounds funny, but I've run into the same thing. Sometimes I can pull a gear far beyond what I would expect, then the next gear, it will bog down far before that same RPM is reached.

Hit me up on PM, maybe we can hammer it out.