I have a DC sports header on my H23 and a Pace Setter Cat Back exhaust, I still have the original cat on the car, and am wondering if there is any difference between a say magna-flow high flow cat, and others, and what would possibly be the best kind to get. I've notices a bit better gas milage with the exhaust and AEM cai i put on over the winter, i figured the high flow cat would help even more.

 

Magnaflow is probably going to be your safest pick. They maintain emmissions and flow better than stock. Also universal.

As far as fuel economy, it will help too. As long as your not hard on the accelerator, these things that allow the motor to be more efficient would actually cause bonuses in gas mileage. But chances are when people install performance parts, they are doing so to enjoy ...."spirited runs".

Depending on your emmission standards you could run open cat for performance too. If I was you I'd get flanges welded onto your magnaflow to make it bolt on. Than you could run an open cat, than change it your magnaflow when your doing emmissions. That would only be okay if the car was...ahem a track car though lol.

 

You can order a magnaflow from Kteller but dont get the one with flanges, all they will give you is some geniric *** 3 bolt flange that wont actually bolt up to your downpipe.

 

Just gut out your stock cat...

 

"Just gut out your stock cat..."
Turbulance FTL