Low Psi vs Pulley Combo

[5PNTSLW]

Wanted to see if anybody could give me some insight/direction to look into.

I have an 03 cobra i just got re-tuned for a return style fuel sys,made 610whp/622wtq @ 16-17psi. Tuner confirmed the PSI with his dyno gauge, and my aftermarket guage reads the same.

KB 2.6, 3.1" upper and a metco 2lb lower(measures 8.1")

8.1/3.1 = 2.6129 ratio

According to KB that pulley ratio should put me in the ~23PSI range correct?


2.6129 ratio X 6500 RPM = 16983.85 blower RPM

And according to the max RPM for the blower (18k), i have almost maxed out the RPM.

No belt slip seen or recorded in a log, car hauls and runs good, just not sure how the PSI for the setup make sense. I believe the power level makes sense for the PSI, just not the pulley combo.

Mods that may matter:
Factory engine, Accufab 120mm TB, Bassani hi-flow catted xpipe, Metco Dual bearing pulley kit.

Any thoughts? Any input would be much appreciated.

 

[01yellercobra]

Is the Bassani mid pipe the only exhaust part you've changed? Stock manifolds and catback?

 

[5PNTSLW]

stock mani's, bassani catback(2.5).

 

[01yellercobra]

For low boost I usually start with check all the inlet connections. If they're all tight then I move on to the BPV. Chances are it's not sealing and bleeding boost off.