Benefits?

[99Camaro99]

For a N/A 3.8 would this kind of exhaust be beneficial:

stock y pipe and headers
3" Catco
2 45deg mandrel bent pipes
2.75" I-pipe
2.75" over axle pipe
dynomax turbo muffler 2.5 in 2.5dual out

if I wanted to add N2O in the future all I would need to do is swap exhaust out, right?

I'm keeping the exhaust at 2.5" so I can still have some backpressure but the engine is still able to breathe better. Opinions please!!!

[Patrick Javert]

first, why would you get a 3" cat if you're gonna run only 2.5" pipe? If you are planning on getting heads/cam, over 100 shot Nitrous, and/or sc, I'd get 3" piping. backpressure is good if you're planning on towing something and need good low end torque. Otherwise, just go for 3" pipe since you'll get great hp gains even w/o heads/cam, sc, nitrous, ect.

[wolf]

I would run a 3' cat and 3'I-pipe,and find a muffler with a 3' in/2 2.5' outs

[RacerJ]

<blockquote>quote:</font><hr>Originally posted by Patrick Javert:
first, why would you get a 3" cat if you're gonna run only 2.5" pipe?<hr></blockquote>

Because a 3" cat will flow more than a 2.5", regardless of what piping size you have after it.


So yes, that setup will work fine. But FYI - the "over-the-axle pipe" is technically part of the "intermediate" piping. ("Intermediate" pipe = everything between the cat and the muffler.)

[99Camaro99]

you guys why 3" piping? Fast guys...I mean the top fast ones are not running full 3" piping. BTW NO CAM, NO HEADS, NO SUPERCHARGER for me. Just bolt-ons and possibly nitrous. If I want a fast car I'll save up and get the Z28 so I have a 13sec car to start with. I just want my car to be a little faster than stock so I can whip up on ALL ricers. Esp, those Celica GT-S's.

[RacerJ]

A stock 2.75" Z28 pipe like you listed will work just fine. (And is much more cost effective.)

People on this board are just obsessed lately with doing all 3" piping.

[wolf]

then just run 2.5 all the way :D ,my nova ony runs 2.25 pipes(true dual exhuast),the f-bodes run 2-1-2 exhaust so I figered a bigger I-pipe would be benifical,but that just my opinion :D

[12secondv6]

I have rk sport headers
2.5 inch piping
2.5 in and out catco high flow cat
2.5 s pipe
then it goes to 3 inch edlebrock cat back

[Ttop34]

99Camaro99, with those 3.42 gears and an auto, what rpm's do you drop down to when your racing? With my 3.23 gears and a 5 speed I only drop down to 4,000 rpm's. That's not low end and you won't lose any power by going to 3" or having totally open exhaust at that rpm. That's actually where mine really picks up power. I did lose low end power, under 3,000 rpms or so when I took off the cat but I gained plenty of upper rpm power to make me very happy however it sounds like crap. Sounding better as it gets burned in again though.

If I had it to do all over again and I was just concerned with performance at the track, not sound or constant performace, I would have got a cut out before the cat with a switch to open it up or close it in the car. I would have saved atleast $500, it would have been faster but sounded a lot worse.

Either way I'm sure you'll be happy with swapping up from 2 1/4" pipe.

[Steve Caroccia]

If you want a 3" in and 2.5" out Flowmaster 80 series, I gots one for sell for $65 shipped. cbass300@hotmail.com

[Seppo Kaitainen]

<blockquote>quote:</font><hr>Originally posted by 99Camaro99:
For a N/A 3.8 would this kind of exhaust be beneficial:

stock y pipe and headers
3" Catco
2 45deg mandrel bent pipes
2.75" I-pipe
2.75" over axle pipe
dynomax turbo muffler 2.5 in 2.5dual out

if I wanted to add N2O in the future all I would need to do is swap exhaust out, right?

I'm keeping the exhaust at 2.5" so I can still have some backpressure but the engine is still able to breathe better. Opinions please!!!<hr></blockquote>

Don't listen to Patrick Javert, your planned set up sounds good.

As for the N20... I think you would be able to spray a 50 shot fine, I think a 75 would be pushing it. I think the only thing you would need to swap would be the manifolds to headers. Then you should be able to go to a 75 shot and high.

NOTE: I'm not a N20 expert, James could answer that alot better.

[ May 22, 2002: Message edited by: Seppo Kaitainen ]</p>

[99Camaro99]

ok guys thank you for all your help. Thursday (today) I am going to the muffler shop to get the work done. I've decided that I will go with 2.75" piping for the catback and I AM NOT changing the cat. Hopefully I'll get my wish...no loss in low end, big gains in high end, and a deeper n louder exhaust. [img]smile.gif[/img] I'll keep you all updated when I get back

[Ttop34]

Hope you get this before you go, but you can actually cut the end off your cat and make it open up to 2.75" or even 3". There's undercar pictures on my site if you want to see what I did to mine. You do run the risk of burning up some of the ceramic when welding it back on though, didn't have to worry about that with mine though. I've heard that our stock cat is pretty close to a high flow cat except the crappy 2.25" outlet.

[99Camaro99]

yea I checked your site and I'm leaving now to get it installed. I didn't see it anywhere on your site :( but I'll mention to the muffler guy about opening the cat's outlet. I just hope it doesn't destory my cat since I don't have the money to buy a new one. Wish me luck guys.

[99Camaro99]

nevermind I'm retarded. I was looking at the mods page. I looked at the pics. I'm going to print it and bring it with me to the shop. :D