Hi,

I was looking at my Power Extreme exhaust that i'm going to install next week and was surprised to see that the 3.75" pipe reduces to 2.5" inside the canister. I guess this is why it is one of the quieter exhausts available. I am not too concerned as I am running the mazda motorsports 2.5" 96 spec downpipe and am assuming this set up should work quite well. However if I was going for maximum power I would be considering a different exhaust right now.

Andrew Wojteczko
93 RX7 R1
Greddy PE
Mazda Motorsports Downpipe
Pettit ECU
Koyo Rad
Pettit AST
Autometer Boost/Temp
Simmons OM wheels
87 944 Turbo

 

Yea, it is pretty damn quite until you do a midpipe.

 

I think the muffler on that exhaust looks like *** IMO. To big and the angled edges just look wierd. Thats why I went with the GReddy Jap-spec, should be here friday.

 

If you were going for max power, something like the Apex N1 is going to get you better flow, however a lot of people don't like the sound and loudness of an exhaust like that.

Generally, the more flow, the louder the exhaust.

 

I had an N1 duel and dumped it for a PE. I've noticed little change in the boost. At most maybe a .03 kg/cm2 drop when really beating on it, but that could also be attributed to different testing conditions ect.
The sound is MUCH better. The duel drones under light throttle and resonates like a rusty soup can under 3/4 throttle. By comparison, the PE sounds much deeper and doesn't drone. I miss the howl of the N1 duel at WOT though. Is the N1 duel really less restrictive? The Y-split can't help.