DOC OTIS

iTrader: (9)

Probally a crazy question but has anyone done this? I just bought Kooks 1 7/8 headers w/3 1/2" collectors. They sold me a 3 1/2" into a 4" out y-pipe that is a very nice piece. My problem is I don't know if I want to run a cat-back and think I would rather dump the exhaust before the axle. The car will see plenty of track time and limited street time so I don't want to have to drop the cat-back every time I go to the track. If someone makes a good enough flowing cat-back I would possibly consider taking the weight penalty and just leave it on all the time. The car will have a 427 motor and sprayed on top of it shooting for mid 10's NA and mid 9's on the spray. Is there any way I could run the y-pipe with one muffler and one 4" dump? Sounds pretty stupid to me but if it works I don't care especially since you wouldn't be able to see it. Or do I just get rid of y-pipe and go with a x-pipe set-up like everyone else? Any thoughts or recomendations would be appreciated.

Thanks

4thGENRETARD

I thought about a side dump too. It's a cool idea if the car is mostly track.
I thought about late sixties Vette side pipe. Not on the side but under the pasenger seat before the rear wheel.
Mine is still my daily driver, but soon I hope.
Lots of weight saving there.

Casper9T9

iTrader: (1)

I run a dump at the track and a catback the rest of the time. I had a local exhaust shop modify my Hooker exhaust with bandclamps so it just slips off in minutes. Then I just clamp a turndown on to the y-pipe and drop about 50lbs at the track.

HOTROD98Z

iTrader: (1)

I've seen a lt1 trans am run the setup you are talking about with a turndown on the y-pipe and it sounded pretty mean.

Pro Stock John

iTrader: (34)

Yeah you could try to put a muffler under there.

If you sell the Ypipe let me know, I am looking for one just like that for my Kooks.

I have dual 3.5 oval exhaust with flowmaster mufflers, no tips, and it's the meanest LS1 you ever heard but my neighbours are very sad.

DOC OTIS

iTrader: (9)

any ideas on what kind of muffler?

Pro Stock John

iTrader: (34)

Doc, I have been kicking around the same thing too.

There are a handful of mufflers that are 4" inlet/outlet.

A Dynomax race bullet will flow the best. It will barely muffle at all.

I had a Dynomax Ultraflow round muffler on my old Mufflex and I am wondering if it would fit under the car. I think they make a big round one and a narrower round one.

Magnaflow makes one too but only in stainless.

I might do the exact same setup, how does that Kook Y pipe fit?

H b K l U n A

that or put if you do go catback...go with the 4" mufflex.

DOC OTIS

iTrader: (9)

I have the 4" mufflex cat-back (was on my old set-up), it is very heavy and I wanted to drop that extra weight. Also I am not sure if it will flow enough for my set-up.

I am still going to street this car plenty so I am trying to keep the db's down enough so the cops don't constantly screw with me. I don't think a bullet style muffler will be quiet enough for the street in this city. Not sure if there is enough room under there for a regular muffler though?

Pro Stock John

iTrader: (34)

If you want to sell the Mufflex let me know. Mufflex is like 55-60 lbs fwiw.

Cal

iTrader: (1)

I've been having a hard time getting information on the Mufflex 4" catback; their website is useless. Can you get this system in stainless steel?

Pro Stock John

iTrader: (34)

I don't think so.

Roadrunner 45

iTrader: (1)

I've got the exact setup you're talking about (except I'm using a 3" dual inlet Y with 3.5" outlet). I used a dynomax 6" diameter race muffler and dump it right before the rear axle. The only problem with the 6" dia muffler is that if you want good ground clearance the tunnel will have to be "adjusted" at the rear seat area. A couple whacks (ok more than a couple) with a BFH did the trick. You could use a bullet muffler if you want to avoid clearance issues.

I actually bought both a bullet and the 6" muffler to play with while I was making the exhaust, but the bullet has vrtually no sound absorbing material and the car is 95% street 5% track. Even with the 6" muffler, it is LOUD at WOT, and semi-loud at idle. It'll set off every alarm in a garage- but no noise violation tickets yet.

I'll post some pics if you're interested.

Cal

iTrader: (1)

Roadrunner, that tunnel adjusting with the BFH is exactly what I'm planning on doing! I'd like to see your pictures!

Roadrunner 45

iTrader: (1)

I'll snap some tomorrow- I can't believe it's already dark outside now- fall/winter

FrankSS

iTrader: (18)

ive got what you are talkin about too. hooker LT's, with their y, then a 18" x 4" dynomax bullet and dumped right beind the rear passenger seat. sounds sweet, only had compliments on it. only 1 noise warning, but that was from a cop that doesnt like me too much to say the least. the muffler fits very nice in the tunnel brace, and has plenty of clearance. let me know and ill get a couple of pics for u.

DOC OTIS

iTrader: (9)

Roadrunner and Frank - Thanks for the info! Any pics you have would be great. Post them here, I am sure others would like to see. I am not to worried about the clearence issues your talking about. I am not going to have a back seat and if I need to fab a little its no big deal. My bigest concern is will it flow good enough to run at the track and will it quiet the motor good enough for the street.

Cal

iTrader: (1)

Doc, those are my goals as well. I decided the only way to get great flow AND a reasonably quiet exhaust would be to install a Borla 14 inch XR1 Sportsman with a 4 dia. inlet and outlet. This is a 14"x4"x8" oval with both the inlet and outlet offset to the same side to not interfere with the driveshaft. I figure that way there will be no change in the routing of the tail pipe, just a matter of making room for the body of the muffler. Since my back seat is gone also, I plan to simply saw out the passenger side seat bulge and weld in a flat sheet of metal to make room for the muffler. This will also prevent any loss of ground clearance.

Roadrunner 45

iTrader: (1)

pics are here:

http://f1.pg.photos.yahoo.com/ph/r43...ro&.view=t

Cal

iTrader: (1)

Roadrunner, looks good . . . thanks for posting those up!