I was reading some old threads of hf cats. I was wondering from the people that bought the gotham racing hf cat, how is it holding up? How about the N-tech hf cats too.

 

I have a bonez high flow and it runs great! ive put about 5-7k miles on it and havent had a problem.

 

almost 20k on N-Tech and 6K with no airpump. Holding up good as ever .

 

I have the Gotham Racing one. I put it on at the begining of the Spring last year & it has worked great since then. I've only put about 1500 - 2000 miles on the car since I installed it. The cat has an outlet for the air pump, but it doesn't mate with the sock hose very well. As of now I don't have the AP hooked up ( I didn't have to have emissions this year ), but I will probally try to hook it up before inspection in May.

 

I also have the Gotham Racing hi-flow cat. I put it on last spring also. I have roughly 800 miles on it so far. Fitment was great, no problems there. I removed my Air Pump so nothing is hooked up to the cat in the way of emissions . So far so good!

 

Gotham here also. Fit perfectly with air pump hose. 1000+ miles. Great Mod!!!!!!!

 

N-tech flows very well. I was very happy with mine. I have since switched to an RX7 Store RMP

 

I'll probably be needing a new Cat in the near future, so if you could provide more details, I'd appreciate it. Thanks.

My questions are:

How's the sound? Did any of these Hi-flow Cats drone at freeway speeds? If so, what other exhaust combination did you have? DP? Cat-back?

Did you guys noticed any gains? I read somewhere that the stock Cat was already a hi-flow design and there wouldn't be much gain with aftermarket ones.

 

I have the N-Tech cat. It fits and works nicely. It's much louder than stock but doesn't drone. Cats generally reduce droning in my experience. I have used the N-tech cat with stainless downpipe and Racing Beat Dual and GReddy Ti catbacks. It sounds good with both catbacks and isn't too loud.

My butt dyno sais there was some HP gains but I had boost leaks at the time I got mine. The stock cat is barely over 2 inches with welds in the exhaust stream while most aftermarket cats are a little over 3 inches (80 mm) and much smoother.

I think best bet would be to get a cheap stainless mid pipe and one of these metal cats and have it welded in. You might take a look at some of the metal cat threads.