i might be picking up a comptech catback next weekend. what i wanted to know is should i get a high flow cat for it or is it already free flowing enough?
ive seen a few people on az with high flow cats with that exhaust but is it really needed?

 

not sure if thats where the restriction is. everyone knows that from the cat back is already pretty good.

but you have to consider that if you lose back pressure, you might lose torque too if you do the high flow cat.

 

hes boosted so less back pressure would be good. but an exhaust will give u little to no power added. just sound. our exhaust it already pretty free flowing.

put u can get a high flow cat to help u get some more power.

 

thanks guys can anybody else chime in too?



i know exhaust adds little to no power but whats up with that ATLP exhaust on the 2nd gen tl side. there saying its adding 10hp. hows it so different from the comptech exhaust?
im so tempted to get that but its like $950.

 

diff design? has it been dyno proven? care less if ppl say it added 5-10hp bc u cant feel that and its mostly in ur mind. need dyno numbers then ill believe

 

the vender mr heeltoe posted dyno graphs. all those 2nd and 3rd gens tl guys swear by that exhaust.

 

alright then

 

yea but i dont know if i want to spend the 1k for it lol.

can anybody else chime on the my original question about the high flow cat?

 

I would think a high-flow cat would be beneficial for a S/C setup because I know the cutout at the a-pipe done by Scalbert showed gains. Based on that, I would think better flow = more power, especially on boosted applications.

I have a high-flow magnaflow cat and I "felt" gains. I did not dyno it separately though and I am N/A. I also just purchased Excelerate's 2.5" inlet/outlet high flow cat, but I haven't had a chance to install it.

 

The high-flow cat on a 2nd gen is like a double-edged sword. You get horsepower gains on the topend but you lose quite a bit of torque on the lowend. So its not necessarily good or bad.

 

I remember reading that the gains from the ATLP were done on a TL-P not a TL-S.

I definately recommend getting either a high flow cat or installing a cutout ahead of it. Boost loves to flow, so your only strangling it with the stock cat.

I just got Excellerates 2.5" high flow cat as well, but I dont if Im going to use it anymore. I will need either a 3" exhaust or a cutout. We'll see.

 

with all that being said i think i will get the high flow cat. if i wasnt boosted i probably wouldnt worry about it.

i was thinking of getting excellerates high flow cat as well. if you sell yours ill buy it. what are you doing to need a 3'' exhaust you going turbo?

 

well if he's boosted then getting the high flow cat might be a good idea actually.

its not like he's running a 3" setup. just frees it up a little more which is what you want for FI. NA is another story.

 

Exactly. NA 3.2 Id keep it at 2.5". Boost Id go 3".

OP- Yea, Im going boost. Im most likely going to sell it. I havent installed it, I just opened the box to look at it.

 

Not needed. Save your $ for other things.

 

any particular reason why?

 

cause he's the moderator. nuff said.

no, i mean its not like he's going 3". cause that would be a drastic change. a high flow cat isnt very drastic but he may benefit from the slight reduction in backpressure. it maybe different if he reduced the backpressure a lot (like going 3")

 

I'd say go for it. I have the 2.5 in/out cat and it feels free'er flowing than the RT cat before it. I don't have my stock cat but have the RT and can see if I can get a before and after dyno. I'm boosted btw

 

It's just not needed. Many more mods could be done with the $. If there's a gain NA it's very small. I haven't touched my cat & I dyno 252.

If you have the extra cash & want to try it go ahead but if you simply think you need to get a cat cause it's going to be such a big difference your kidding yourself.

NA that is.. If your boosted it may be a good idea.

 

im boosted

 

If you bought the ATLP exhaust...you'd have to modify it.

I'd say pass on it...

 

For now on I think you need to put in the first post that you are boosted so we can avoid any confusion.

 

yea i knew that but i decided to pass on the atlp.

yea i noticed

 

 

yes get a high flow cat, i got a highflow in on my 01 CL-S it seemed to loose alittle down low like from a dig, but not enough to notice, and i gained what felt like a good bit of top end