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leebo
I'm at the final stages of my CMC camaro build. Last thing, other than Vats issue, is the exhaust.
We have to have the stock y-pipe but after that its open.
My question is what are most people doing?
the easiest would be to turn it out by the passenger door but I think that would be too loud on the occasional rider.
I was thinking of going out the back passenger side using a 6" magnaflow race muffler.
Any suggestions would be appreciated.
Thanks Lee
camaro4cmc
For a quick and easy exhaust system for the 3rd and 4th gen cars you can use parts of commercially available Cat back exhaust systems.
Example: http://www.dynomax.com/part_view.php?syear...&engine=5.7
If you go to this page and open the installation instructions you will find the individual part numbers to the pipes in the kit.
you can buy these pieces separately, saving you money on the parts you don't want and giving you a great staring point with mandrel bent tubing that you won't get at your local muffler shop.
good luck.
Blainefab
QUOTE (leebo @ Aug 26 2013, 10:41 AM) *
I'm at the final stages of my CMC camaro build. Last thing, other than Vats issue, is the exhaust.
We have to have the stock y-pipe but after that its open.
My question is what are most people doing?
the easiest would be to turn it out by the passenger door but I think that would be too loud on the occasional rider.
I was thinking of going out the back passenger side using a 6" magnaflow race muffler.
Any suggestions would be appreciated.
Thanks Lee



Cut the OEM intermediate pipe just before it bends up over the axle, weld on a bullet muffler with a turndown just ahead of the axle. Add a strap hanger up to the body. Pound in the rear passenger buttwell for muffler clearance.
leebo
Thanks Guys!
Blainefab
QUOTE (Blainefab @ Aug 26 2013, 04:01 PM) *
QUOTE (leebo @ Aug 26 2013, 10:41 AM) *
I'm at the final stages of my CMC camaro build. Last thing, other than Vats issue, is the exhaust.
We have to have the stock y-pipe but after that its open.
My question is what are most people doing?
the easiest would be to turn it out by the passenger door but I think that would be too loud on the occasional rider.
I was thinking of going out the back passenger side using a 6" magnaflow race muffler.
Any suggestions would be appreciated.
Thanks Lee



Cut the OEM intermediate pipe just before it bends up over the axle, weld on a bullet muffler with a turndown just ahead of the axle. Add a strap hanger up to the body. Pound in the rear passenger buttwell for muffler clearance.


I found a pic - This is a complete LT1 CMC system using the OEM Y and intermediate with a 3" 2chamber FM, the turndown is just ahead of the axle.

Steve91T
The stock Y pipe is not required. Only the stock manifolds.
Blainefab
QUOTE (Steve91T @ Aug 26 2013, 08:46 PM) *
The stock Y pipe is not required. Only the stock manifolds.



That is true - but, the LT1 will make 260rwhp with the stock Ypipe so no need to spend money to replace it, and then have to restrict the intake to get the HP down. Also, larger dia aftermarket Ypipes typically end up closer to the oil pan than the stock one, dumping exhaust heat into the oil.
Steve91T
QUOTE (Blainefab @ Aug 27 2013, 01:08 AM) *
QUOTE (Steve91T @ Aug 26 2013, 08:46 PM) *
The stock Y pipe is not required. Only the stock manifolds.



That is true - but, the LT1 will make 260rwhp with the stock Ypipe so no need to spend money to replace it, and then have to restrict the intake to get the HP down. Also, larger dia aftermarket Ypipes typically end up closer to the oil pan than the stock one, dumping exhaust heat into the oil.


For some reason, my stock Y pipe touches the Canton oil pan. Not sure how to fix it other than smashing the crap out of the Y pipe to try to clearance it.
DAlgozine
I'm working on this right now on my car (98 Camaro). I have a stock style Y pipe, and I'm still scratching my head about where to go from there. I'm not a fan of turn downs. In the past I have had exhaust fumes find there way back into the car with turn downs, and depending on the muffler, it can be pretty loud in the car. Then there is the issue of heat.
Originally, I picked up a used aftermarket cat back system, but I have a fuel cell, and there is not enough room for the crossover behind the diff.
I've been looking at piecing together a bullet type muffler , then a 90 to a boom tube that will exit just in front of the passenger rear tire, similar to a stock car. Boom tubes are very thin (1 1/2" ) and only 8" wide. Pretty sure I could put this together for just a little more money then a bullet muffler and having a local shop bend pipe over the axle and exit the rear.
Anyone done or seen something like this on a late model F body?
Steve91T
QUOTE (DAlgozine @ Aug 27 2013, 11:51 AM) *
I'm working on this right now on my car (98 Camaro). I have a stock style Y pipe, and I'm still scratching my head about where to go from there. I'm not a fan of turn downs. In the past I have had exhaust fumes find there way back into the car with turn downs, and depending on the muffler, it can be pretty loud in the car. Then there is the issue of heat.
Originally, I picked up a used aftermarket cat back system, but I have a fuel cell, and there is not enough room for the crossover behind the diff.
I've been looking at piecing together a bullet type muffler , then a 90 to a boom tube that will exit just in front of the passenger rear tire, similar to a stock car. Boom tubes are very thin (1 1/2" ) and only 8" wide. Pretty sure I could put this together for just a little more money then a bullet muffler and having a local shop bend pipe over the axle and exit the rear.
Anyone done or seen something like this on a late model F body?



I've been thinking of doing something similar except using a piece of 3" oval tubing. That would weigh less and would be cheaper. I don't think you need a huge boom tube. You'd have to get the exhaust out past the tire to keep from heating the tire.

I wonder if coming out the side is better than dumping before the axle as far as fumes are concerned.
DAlgozine
QUOTE (Steve91T @ Sep 1 2013, 07:50 PM) *
QUOTE (DAlgozine @ Aug 27 2013, 11:51 AM) *
I'm working on this right now on my car (98 Camaro). I have a stock style Y pipe, and I'm still scratching my head about where to go from there. I'm not a fan of turn downs. In the past I have had exhaust fumes find there way back into the car with turn downs, and depending on the muffler, it can be pretty loud in the car. Then there is the issue of heat.
Originally, I picked up a used aftermarket cat back system, but I have a fuel cell, and there is not enough room for the crossover behind the diff.
I've been looking at piecing together a bullet type muffler , then a 90 to a boom tube that will exit just in front of the passenger rear tire, similar to a stock car. Boom tubes are very thin (1 1/2" ) and only 8" wide. Pretty sure I could put this together for just a little more money then a bullet muffler and having a local shop bend pipe over the axle and exit the rear.
Anyone done or seen something like this on a late model F body?



I've been thinking of doing something similar except using a piece of 3" oval tubing. That would weigh less and would be cheaper. I don't think you need a huge boom tube. You'd have to get the exhaust out past the tire to keep from heating the tire.

I wonder if coming out the side is better than dumping before the axle as far as fumes are concerned.


I just bought all the components and plan to install them early next week. I'll let you know how it goes.
Dr Gas sells a boom tube with a muffler built into the interior. Its cheaper then a typical aftermarket cat back.
Steve91T
Dr Gas is still around? I haven't been able to find his site anymore.
mr.beachcomber
Try this link! beerchug.gif
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