More power with or without cats?????

[Z O SICK]

Hi i have a bassani X pipe with removeable cats. Will i get more HP/TQ with or without cats. I heard that taking off my cats will kill my low end TQ but i will get more top end power. What are the pros/cons to having or not having cats.

Thanks,
Tony

 

[PhillyCobra]

Pretty much as you say. Some loss torque down low, some gain up high particularly if you have a modded engine.

Downsides are 1) you're illegal and polluting the environment,
2) it smells bad unless you like the smell of gasoline and 3) might sound worse to you (to others might sound better)-- will be louder.

 

[BADASS03SVT]

a guy in the new england area ust did this. he went from a catted x to an o/r x and dynoed...lost 20hp and like 20ft/lbs and is car went WAY lean....

 

[RUgoinup?]

When I bought my Cobra, it came without cats (homemade h-pipe). I recently replaced it with the stock h-pipe that Sam @ Coastal Dyno gave me (and installed) free of charge (Thanks Bud!), and the car felt like it picked up 20hp.

 

[ghostrydyr]

I tried both

@ the track

mods=cia & catback best trap spees was 110mph

mods=cia, catback and an off road X pipe best trap was 112mph

These #'s seems slow but I go to a known slow track (SearsPoint raceway). The car obviously was faster with out the cats but it lost torque down below. You will notice the lost of torque on the street.

 

[ghostrydyr]

Oh yeah btw it will lean you out about 1 point.

 

[Z O SICK]

Thanks for the helps guys. I guess i will just leave the cats on. I love my low end TQ. I also have an Apten on the way and i think that will help me out up top.

Tony

 

[JaketheSnake]

Originally posted by RUgoinup?
When I bought my Cobra, it came without cats (homemade h-pipe). I recently replaced it with the stock h-pipe that Sam @ Coastal Dyno gave me (and installed) free of charge (Thanks Bud!), and the car felt like it picked up 20hp.

dont forget to thanks me as well b/c thats my old hpipe!!! :beer:

 

[jackers]

where did you get the bassani x with removable cats. i cant find one anywhere. and how much did you spend for it?

 

[Juiced-03]

I took my cats off my Magnaflow X pipe and felt a definite increase in power up top. Feels like it breathes much better. Didn't lose any torque down low either. Still shreds the tires in second gear from a low punch

 

[Z O SICK]

I got my X at RPM outlet.

Tony

Originally posted by JaketheSnake
dont forget to thanks me as well b/c thats my old hpipe!!! :beer:

 

[jasonc32amg]

there's no gas smell without the cats...and my car doesn't suffer a deficit of low end torque...

 

[tv's 03]

I would doubt you will lose any low end with a o/r H but gain some power almost everywhere

 

[Z O SICK]

Well it looks like some say i will loose some low end and some say i wont. I guess i will just have to try it out for my self

 

[memphisstang]

I think "ghostrydyr" is right on this one. You usually pic up some power up top, and some time at the track(never heard of anyone that lost either by loosing their cats). On the other hand, it has also been my personal experience that you loose seat of the pants feel when loosing your cats, and you gain some noise. I guess it comes down to which is more important to you-daily driving quality or max time at the track.
By the way "RUgoinup?", I like your sig!!!

 

[notdisturbed]

I dont think its a matter of "losing" HP, or "gaining" HP anywhere in the band. Instead, its just like what happens when you up your exhaust diamater, it just shifts the torque band over on the RPM range. You're still getting all that torque, it just comes on a little later due to the higher flow. As for me, my last dyno showed my torque at around 365 ft.lbs. at 2100 rpms, which to me is plenty to risk moving the torque band up a little, so im thinkin about yankin my cats.

 

[combatstang]

I have always wondered this!!!

Kills me

Marc

 

[Pssssss_oh3]

gained 20 hp

keep the catz...JSTA46...
What Intake??I'll let yall in on a secret.

 

[Miamifan1354]

With cats on, you have better back pressure, and that means more boost, and more HP..

I got about 15 HP from having the cats ON!

 

[Torch10th]

Originally posted by Miamifan1354
With cats on, you have better back pressure, and that means more boost, and more HP..

I got about 15 HP from having the cats ON!

Boost itself does not equate to more power. Your engine is a big air pump, the more you can flow out of it the more power you make. more back pressure is not what makes more power. You want your exhaust to be as free flowing as possible while still maintaining good velocity to promote scavanging.

Boost is nothing more than a pressure indicating at the intake manifold. If you put a 2.8 pulley on a stock headed, cammed, exhaust car, vs a car with some ported heads, slightly larger cams, and an exhaust the stock car would make more boost. However the car with the worked heads, cams and exhaust would run away from the Cobra that is making more boost.