how much if any improvement would a test pipe or high flow cat make? is it worth the money? Thanks

 

high flow cat....hp depends on setup and if the car is N/A or FI
i have it on my turbo

 

If you already have a header & exhaust then this may make sense. You'll probably pick up a few ponies. Test pipes are better, but illegal on the street, lead to CELs, and stink. Your call.

 

yea my engine mods are, i/h/e/cam gears, yea so whats the down sides to the test pipe? Any idea where i could get a good deal on one or on a high flow?Thanks

 

test pipes hardly flow any better than a quality high flow cat.

High flow cats also don't smell, don't trip a cel, and don't pollute. Go for a highflow cat, the difference is pretty minimal.

 

i got high flow cat from Ipsracing.com from Mike M
ok. down sides of test pipe is that well its illegal and some state if you get caught fine is very high. you will get few more hps from it then cat but i dont think it is worth it if your car is daily driving.

 

i got mine from MIKE also at isp...he's got good deals going on.

 

I got both a test pipe and cat from SMSP

 

Carsound from IPS, or SMSP(smsp has the bottleneck remover as an option)

 

so the gains are worth the cost? anyone have any dyno proof of the power improvment? if so how many around 2-3hp or so?

 

I have seen a dyno of a carsound cat vs a testpipe, and there wasn't even a 2hp difference. The slight difference that there was, could have been attributed to heat difference.

I will try and see if I can dig it up.

 

really? humm anyone know anything about the obx cat? i mean 50 bucks is a nice price. So with even the best of high flows whats the dyno'd improvement you've seen?

 

Engine building is not like legos, everything works together and effects each other as a system. A high flow cat is going to make a larger difference for an engine that has cams/high compression/etc, because at that point it is a huge bottle neck, than one that has boltons only.

A highflow cat is an essential part of an exhaust system, and you are losing performance if you stick with stock.

Beyond the diameter difference (1.8 ID instead of 2.25" or bigger) the flow is terrible.


Testpipe in red, carsound cat in blue.

Huge difference eh?

 

carsound cat makes more tq

but in general, you can just see that the do the same thing powerwise, legally with the cat, illegally with the TP. I had a test pipe and it gave me a guiltry conscience too...eek.

 

HIGH FLOW CAT ON THE STREETS

please don't contribute to air pollution.. what if one day we all got lung cancer from the air we breathe? Then would you still get a testpipe?

 

go with car sound cats

 

getting busted with no cat is priceless


[Modified by LS-T, 10:55 PM 3/5/2003]

 

I personally hollowed out my cat, and I must say I'm planning on replacing it w/a high flow cat. If you are ever behind a car w/o a Cat you will know it. The smell is just unmistakable.

 

hollowing out your cat is still bad for performance, because the diameters are still all mismatched.

For example, if you have I/H/E, and a hollow cat.

Chances are you go from a 2" collector, to a 1.8" inlet on the cat, to a 2.0" outlet on the cat, to a 2.25" or bigger exhaust. All that stepping down/up is going to kill flow quality and reduce exhaust velocity and performance.

 

I think i may be getting a obx 2.5' high flow, for $50. Just in case any comments, downsides etc? Thanks

 

The only comment I'd have is that typically OBX parts are of very low quality. Who knows maybe they make awsome cats.