Poor Acceleratgion At Low Rpm

[gibby]

I have a 2004 996 C4S and I put in Fab speed 996 Sport Catalytic Converter X-Pipe and now the acceleration is not as brisk as it could be till it reaches 3500 rpms and then it kits in and is very fast. What would cause this? There are no faults in the computer.

I know if I put the factory cats on the problem will go away but the performance wont br there.

Further to this.

I was told by Fab Speed that if I have the ECU recalibrated that it would solve this problem. Anyone have any experience with is ??

Can U recalibrate to balance the air pressure?

Thanks

[flyingpenguin]

I have a 2004 996 C4S and I put in Fab speed 996 Sport Catalytic Converter X-Pipe and now the acceleration is not as brisk as it could be till it reaches 3500 rpms and then it kits in and is very fast. What would cause this? There are no faults in the computer.

I know if I put the factory cats on the problem will go away but the performance wont br there.

Further to this.

I was told by Fab Speed that if I have the ECU recalibrated that it would solve this problem. Anyone have any experience with is ??

Can U recalibrate to balance the air pressure?

Thanks

Fab Speed's advise is sound. The mods resulted in reduced back pressure which affects torque, which is especially noticable at lower rpm's.

I did not go the Fab Speed route (just cobbled some parts together at intake and exhaust), and experienced a similar problem. This was fixed with Scot Slauson's Softronic tuning solution. They do a good job customizing the ECU mappings to your needs.

www.softronic.us (no affiliation).

JP