Mac hi flow cats ... Hp ?

[Pops Fun]

Hi
I want to quiet down my 94 with Dynomax Ultra Flo SS Exhaust

Thinking about putting my Mac hiflow cats back on and wondering how much HP I would lose???

565 rwhp... changing from a cobra intake with a 65mm T/B to a Systemax with a 75mm T/B hoping to make 600 horses and wondering how much you thought the Mac hiflow exhaust would hurt.

 

[VibrantRedGT]

This is going to sound weird but the truth. Back in 1997 in the state of Florida we still had emission testing. My car at the time did not have heads and cam yet (Edelbrock Intake, 70MM TB, Headers, Pulley's, etc.). I ran a 2.5" MAC high flow catted H-Pipe and also ran a MAC off road H-Pipe. After emission testing I'd put the off road on. Anyway there was a local dyno day and at the time I had the high flow catted pipe on the car, it made 241HP / 292TQ. I went home and installed the off road pipe, went back to the dyno, it made 237HP / 289TQ. The catted pipe made more HP and TQ. This is on a 240HP though. I sold the pipe after the emission testing was no longer in Florida.

I think it'll quiet down the car a bit. Since you're making some serious HP it may rob some power. It's undetermined how much until you dyno it.

 

[revhead347]

That Ultraflow SS kit can't be beat for the money. Just installed one not long ago. I think you are making a little too much power to go back to cats now. If you decide to do so, get some really nice ones.

Kurt

 

[Pops Fun]

Personally I think the HP/airflow will kill any muffler I put on.... Had them in the garage attic... so think I will try the cats and see what happens.
Just getting to loud... Feel like every time I hit the throttle the cops can hear the car blocks away..

Not fun worrying about a ticket.

 

[earleys94gt]

With the power your making, I don't see a couple of cats hindering the performance all that much.