Guys please help i have problem on RXP

I have RR ECU 8800
60lb injectors
Walbro fuel pump

On Peak RPMs on straight line sometimes gas is out and engine work as with 2 cylinders. Its about 10-30 sec. Write 1690 and after 1511 or 1517.
After 10-30 sec everything is ok. Ride again. In sometimes again on peak RPms.

Im ride without VTS its off stay only wires.

Thank you