I know it takes special custom fabrication to get a good true dual set up for the ls1 camaro (mine is a 2000) but is it better to just run cut outs after headers? my car is completely stock right now, here is the plan: Pacesetter LongTubes into cutouts, into y-pipe, into magnaflow muffler, out the tips. I also live in NC, so we have emissions...can the cats go after the cutouts? Also, what kind of power do you get to the wheels if you have cut outs right after the headers to bypass the rest of the exhaust system? How many people have run this set up before, and how much did it cost in labor to install, and how GOOD does it sound? Thanks everyone..

 

Whether you do true duals or dual cutouts, you'll see pretty close figures. I guess the main thing would be making sure you have enough space to run the cutouts before the catalytic converters. My friend has the LTs and catted y-pipe on his LS1 but I haven't been under it in awhile so I cannot get a visual idea in my head of what kind of space you have to work with.

 

is it possible to run the cut outs after long tubes, then cat the y-pipe? only have to worry about buying one cat then (or re-using the old one) and wont have to worry about space constrictions so much...or do you need to run cats right after the cut outs and before the ypipe... thanks

 

Well, if you run one cat, you are going to have to put it further downstream on the exhaust, where the two pipes join into one. Back there, the cat will not be as effective as it will have a harder time heating up. As for reusing an old cat, that is not feasible either considering the differences in diameter of the piping.

 

assuming i go with the cutouts, that would be a almost a completely free-flowing exhaust, or about as close as i could get....any idea what kind of power gain that yields with the normal cold air intake assemblies out there?

 

with just a bolton motor...i bet you wouldn't see much gain with dual cutouts over a single cutout.
figure 15hp assuming you were going from bone stock exhaust.

you may get 2-3 more hp with dual cutouts...but you'll also lose ground clearance and have an anoyingly loud car.

if you're not planning on cam or h/c in the future...stick with a simple ypipe, single cutout and a good 3" catback. the magnaflow is a great choice.

 

Alrighty how does this sound to you guys...let me know what you think the sound will be like!

Flotech LT's (From Advance) --> Y-pipe --> Cat Conv. --> Cutout --> Magnaflow or Borla Muffler --> Stock tips and tailpipes

Or should I put the cutout before the cat? And will this single cat pass the emissions in NC, since they apparently only do visual?

I really don't feel like buying an entire cat-back, unless there is some huge advantage to it...should I just leave the regular stock piping on there in place since.....its...already there?

 

You probably won't have space to put the cutout right after the cat, but I could be wrong. Right before the rear axle is a good place though. If you have the cutout open, having a full catback isn't as essential. If you didn't plan on having the cutout whatsoever, then having a full catback with the larger intermediate piping would have some advantage.

 

Yea the stock piping can be restrictive but with mandrel bent 3 inch piping you will notice a big difference.

 

a single 3" cat on an LS1.....um...NO. even a high flow unit will choke the motor down.

if you have to pass visual, LTs won't pass probably. unless all t hey look for is a cat(s).

you'd be better off putting 2 cats on the ypipe (or buying a catted unit).

then put 3" pipe from the Ypipe back to a a cutout, then whatever exhaust behind that you like...since the cutout will take care of performance.

 

Just curious...but how does putting two cats on a y-pipe differ from just putting one? If just putting one is so restrictive, what keeps the first of two from being restrictive?

 

not sure if i'm reading you right.

by 2 cats i mean one on each side of the Y, after each header collector.

cats are by nature restrictive, the exhaust has to pass through a honey-comb material that is the heart of the converter. having to do that restricts flow.

by putting 2 on the car, you're only forcing 1/2 the exhaust gas volume through the restriction, compared to 100% of the flow through one.

its a physics thing...

 

I know how the cats work and how restrictive they are and the benefit to having one on each end of the y-pipe, but the way you said it earlier sounded like you recommended putting one at the junction of the y, then put another right after the first one. I think I will go with some true dual setup dumping before the rear axle...has anyone done that with about 3" pipes and maintained a good amount of ground clearance?

 

if your state only runs visual inspections. you can take an old cat and a big metal pry bar or somthing and break all the insides out of it. did that with the stock cats on my LT1 and it worked fine, sounded good too

 

i've got duals on my car, 3" with an Xpipe and magnaflow 4x9 mufflers dumped.

clearance is good considering its 3" and i did it myself on my back in the driveway (except the final welding).

the driver side is a bit lower, had to have it welded up in a hurry...a hurricane was coming....so i didn't get a chance to tweak it 100%.


i know this is from a distance, but it gives an idea of the clearance


got more pics...but i need to get them into cyberspace