Switched from MP to hi-flo cat = amazing improvement (w/ non-sequentials)
 

Yesterday I switched out my midpipe with a hi-flo cat and couldn't believe the difference in acceleration. You would think it would be the other way around. I couldn't stand how loud the MP was and I had NO bottom end at all - especially with non-sequential. But with the hi-flo my turbos spool up much faster and it pulls much harder. I'm still in my break-in period with a new engine so I haven't tested it over 4000 rpms (when the real power comes on with the non-sequentials) I can't wait to get this engine over 1000 miles. I was looking at some dyno runs with a FD w/ MP and then with a hi-flo. The car had more power (alot more) with the hi-flo all the way to 6K rpms then power dropped off. With the MP it was laggy until 6K but then the curve went straight up and averaged about 30 more whp after 6K. I drive around town alot and the hi-flo was definitely the ticket. This thing pulls very hard and is much quieter - almost sounds like a Porsche :D

Hmmm, interesting. I came by a SS Pettit midpipe for free, so I decided to install it. I love the sound (and the stink :D ) but I feel like I've lost a lot of low end. Pulls like a rat bastard above 6k, though. I'm thinking about putting the stock cat back on and seeing what I dyno at. The stock cat is just so damn heavy compared to the m/p. I think I saved 50 lbs. just by making the swap...

I looked at the new Turbo magazine the other day...It had a black FD with 400 whp with a high flow CAT..it passed smog test at low and high throttle. It has a remote air pump that pushes air into key locations along the exhaust. I was wondering if anyone had any info on this air pump.

400 rwhp emissions-legal FD...
 

That's Chris Ott's car from RP in Texas. I'll see him tomorrow in Houston; I'll ask him about the air pump. I do know the car retains the stock ECU to handle emissions and has a Haltec for everything else. Chris told me it was a pain in the ass to set the car up, but they did it just to prove an emissions-legal monster FD could be built.

i think he has an electric airpump from a corvette!