I have long tube headers and the Borla TD installed.
I think that the very low backpressure takes some hp from the
system.
From runs I had before the headers and after I can only say that
there is no improvement in acceleration.
I think either NA and SC applications need some backpressure for
maximum hp output.
Only Turbo engines run the best with 0 backpressure.
Any ideas?

 

how long ago did you install? it takes a few days sometimes to adjust for the additional air flow. i like the effect of my xerds and injen and think it made a huge difference in mid range power

 

I installed them some time ago. I ran about 800miles on the racetrack since then.
The mid range is exactly where I think I lost some power.
??

 

do you have any way of controlling your a/f. my car was losing power due to the knock sensor pulling timing from it running lean. ever since i installed my afc and tuned, it feels much better now. have you dynoed?

 

Haven't dynoed.
Tuning an SAFC is not that easy in here. I'd like to have it done however.
Maybe I should send the ECU to TS. That would be the easiest.
Do they adjust the fuel settings or just care for timing and rev limit?

 

I believe every setup needs backpressure. In the case of turbos, the actual turbines to the turbo typically provide adequate backpressure.

 

...talking about backpressure from exhaust systems.

 

What is the diameter of the piping where the xerd connects to the y-pipe? Let's say I have 2.5inch piping throughout my exhaust all the way to the cats, then when the xerd replaces the cats will it fit?

 

I believe the collectors are 2.25" and the primaries are 1.75"