Hi-Flow Cats vs. Resonated Cat Pipes
 

I'm new to the tuning market. So can somebody explain to me what the differences between resonated vs. non-resonated test pipes, high flow cats, and long tube headers are? I'm looking for something that will give the largest horsepower gain, but I am confused on what to get.

Test pipes give you the largest gains in HP but you lose torque. HFC's are needed if you live in a state where inspections are done. I would suggest Motordyne ART pipes as you'll gain a lot of HP AND TORQUE!

Largest HP (Less retrictive)=Test Pipes
Street legal and somewhat quieter=High Flow Cats

Resonaters reduce "rasp" and "drone" noises from opening up the exhaust.

Here's about as good a breakdown as I can make away from home:

Stock Cats

• Suck

High Flow Cats (HFC's)

• Either Ceramic or Metallic Core - You'll want Ceramic, last longer, least prone to core ruptures
• Better flow than stock cats, but less than test pipes or headers
• 50/50 chance of passing sniffer tests
• Still retain 'Stock' look for visual tests
• Mild HP/TQ gain

(Resonated) Test Pipes

• No Cat whatsoever
• Will NOT pass sniffer tests
• Better flow than Stock/HFCs, but less cleanly than headers or ART pipes
• Resonated TPs will have less rasp/drone than Non-Res but performance is unaffected
• Moderate HP/TQ gain

Advanced Resonance Test Pipes (ART Pipes)

• No Cat whatsoever
• Will NOT pass sniffer tests
• Improved flow over regular (R)TP's
• Slightly nulled rasp, but still noticeable
• Slightly more HP/TQ output than regular (R)TP's

Long Tube Headers (LTH's)

• Sex
• As with (R)TPs and ART Pipes, no cat whatsoever
• Smoother flow than all previously mentioned parts
• Distinctive sound, slightly higher pitched yet quieter idle
• Most Dyno proven gains out of the group.
• Hardest Install of the bunch, but looks the best when completed.

Hope this helps with the basic idea. :tiphat:

Sounds about right Chris. LTH are expensive though and my only other argument is the ART pipes with an aftermarket header would put out more power than the just regular LTH because of the ART pipe design and would still cost less. This is just a theory because LTH are just a regular test pipe and header in one piece and the ART pipe is better than a regular test pipe, therefore it should give better results when mated to a header.

Isn't it like 5-6 hours for a shop to install headers?

OP, you're going to have to look into the emissions laws in your area to decide how you'd like to approach your mods. If they do inspections you'll have to stick to HFC's or make buddies with a shop like I did in New York and I was able to run around with limo tint on my car.

great break down man, :).. But headers have been said to be not worth the $$$ or the install time for the WHP you get (At least over on G37.com) .. I would only go either HFC or ART pipes.

Thanks for the help Chris that really makes it simple for me!

Any thoughts on Fast Intentions' "Resonated Cat Pipes"? From what I understand, they're HFC with a resonator. So, you get the performance of a HFC with the added "silencing" of a resonator. But wouldn't the resonator cause restriction, therefore defeating the purpose?

Yes and no. The cells inside the HFC are less restrictive than stock, and the resonator they use is probably a high flow model.

Great question!

Our resonators are straight through perforated core. No baffles or louvers. They do not hinder the performance at all!

So to answer your question, the added resonator is strictly designed to cut down the sound.

If you have any questions or would like to place an order, please do not hesitate to call me directly...

Thank you, Tony

Is Berk the only brand that utilizes the stock brackets?

I wouldn't worry about the brackets. Originally my berk cats were installed with the bracket but it ended up making a lot of noise. Removed it for a weight savings mod!

Noise? I would expect the bracket to prevent vibration and movement. Weird.

It was weird. The noise would only be present during deceleration.

I just learned that the CNT test pipes has the bracket mounts too.