Problems with Fuel Pump and Tank| RACING RX8

Hi friends ... glad to stay here. Maybe u can help me.
I've a RX8 2010 MT / 78.000 km (48750 miles) and i use it for racing competition.

Some upgrades that i have:

- HKS Hypermax III Coils
- Front Stop Disks DBA 5500
- HP Plus BrakePads
- Racing Beat Intake
- Racing Beat aluminium stop lines
- BHR Ignition System
- NGK plugs
- HKS Exhaust System
- Exhaust Header Jasma
- Fiber Carbon rear Spoiler
- Fiber Carbon hood
- Light weight trunk
- Royal Purple 10w40 XPR
- Idemitsu Premix

Buuut! I've a problem at the moment of accelerate ... with my team are sure the problem is in the fuelp pump or tank.

We´re thinking in change the fuel tank and pump ... but we dont know how to do that ... :( the season starts on March and i need a solution asap! :(

Can anybody help me?

Problems with Fuel Pump and Tank| RACING RX8