custom Camaro exhaust idea, comments please!
Posted: Fri Aug 07, 2009 5:52 pm
Q: Why am I designing this in the first place?
A: When I get a Camaro Z28, I want to smooth the burble out of the LT1's natural tendency at idle into a very unique sound for a Camaro. I might as well do the research now rather than when it is sitting somewhere waiting for work to be done.
Anyway... on with the show...
This is the way a stock Camaro Z28 looks underneath. For '96 and '97 there was an additional catalytic converter directly on the driver's side manifold. From '93 to '95, the cars only had the single cat mounted under the legs of the front seat passenger, I believe the cat used from '93 to '95 was more restrictive than the ones used '96 and '97 because the dual cats bumped hp up by 10 hp.
After the catalytic converter under the passenger, the exhaust goes to a Y-pipe and from then on travels to the muffler as one single 3" pipe instead of two 2.5" pipes. Once it gets to the muffler, it splits off into dual exits and you have your dual exhaust.
Some people want true dual exhaust, and don't like the Y-pipe and instead go with an X-pipe or H-pipe. They usually remove the cats altogether.
Most people who use an X pipe on Camaros are typically drag racers who run the plumbing down the center of the car--Camaros aren't made for that. 90% of them have the mufflers mounted mid-ship and have them dump before the axle to avoid the major clearance issues dual 3" pipes run into when going over the axle. Some manage to find ways to run the pipes out the back by relocating suspension/driveshaft/etc. parts. Either way, they sacrifice a lot of ground clearance, but drag racers don't care, because they don't have lowered cars usually.
This guy has more ground clearance overall, but still has the pipes running through the center of the car (can't see them too well in this pic unless you look for them in the darker area of the photo), but he was smart and mounted some extremely thin mufflers along the outside of the underside of the trunk (or as I call it... the pit... because it is very, very deep for a trunk). So he only has about 3 inches less ground clearance instead of 4 or 5 inches like the guy above.
An idea that works even better (in my opinion) is to go alongside the passenger side of the car (like the stock exhaust plumbing), go over the axle with both pipes where the stock plumbing does, put a dual inlet/dual outlet muffler (same size as stock or likely smaller to accommodate the extra pipe that will take up space there) where the stock muffler normally goes, and then run two exits on the driver's side, or do what this guy below did. This way you don't sacrifice but maybe an inch or two of ground clearance in certain areas if any at all!
All three of the above applications have 1 thing in common: they are all illegal modifications. They won't pass inspection, because they took off the catalytic converters, they don't have O2 sensor(s), and besides that, it's illegal to change the location of the cats, which is why most aftermarket exhausts are cat-backs. I want my car to pass emissions without a single issue, so there's no way I would do exactly what these guys did.
My idea is to keep the stock Z28 exhaust manifolds and stock cats. Everything after that will be changed. Now here's the interesting part...
The Maserati Gran Turismo S has an extremely beautiful exhaust note. It is a nice humming sound at idle, and when revved, it releases a bark. Ex: http://www.youtube.com/watch?v=XuiH4zPCONU The way it apparently does this is through the use of a resonator mounted just after the cats and well before the mufflers. The mufflers are a very interesting shape and likely have something major to do with the sound as well, however, what is important here is that the resonator is what blends the combustion cycle into a nice even hum, and when revved, the gasses are moving too fast to be subdued by it. Camaros do not have a resonator. Mine will.
Gran Turismo (not S version) cats, resonator AKA central muffler according to Maserati, and plumbing:
Gran Turismo S mufflers AKA silencers according to Maserati:
I looked into it, and I can get the 'central muffler' which is actually a resonator combined with an x-pipe for about $538 online. Pricey. I can probably get it locally much cheaper (or even free?) from the Maserati dealership when they install aftermarket exhaust on a Gran Turismo or Gran Turismo S (which is sadly common, because then it no longer has the smooth idle, as the aftermarket does NOT use a resonator at all, just an X-pipe). It's #5 in the illustration, and about the length of a loaf of bread I would guess. Probably weighs around 15 pounds.
A: When I get a Camaro Z28, I want to smooth the burble out of the LT1's natural tendency at idle into a very unique sound for a Camaro. I might as well do the research now rather than when it is sitting somewhere waiting for work to be done.
Anyway... on with the show...
This is the way a stock Camaro Z28 looks underneath. For '96 and '97 there was an additional catalytic converter directly on the driver's side manifold. From '93 to '95, the cars only had the single cat mounted under the legs of the front seat passenger, I believe the cat used from '93 to '95 was more restrictive than the ones used '96 and '97 because the dual cats bumped hp up by 10 hp.
After the catalytic converter under the passenger, the exhaust goes to a Y-pipe and from then on travels to the muffler as one single 3" pipe instead of two 2.5" pipes. Once it gets to the muffler, it splits off into dual exits and you have your dual exhaust.
Some people want true dual exhaust, and don't like the Y-pipe and instead go with an X-pipe or H-pipe. They usually remove the cats altogether.
Most people who use an X pipe on Camaros are typically drag racers who run the plumbing down the center of the car--Camaros aren't made for that. 90% of them have the mufflers mounted mid-ship and have them dump before the axle to avoid the major clearance issues dual 3" pipes run into when going over the axle. Some manage to find ways to run the pipes out the back by relocating suspension/driveshaft/etc. parts. Either way, they sacrifice a lot of ground clearance, but drag racers don't care, because they don't have lowered cars usually.
This guy has more ground clearance overall, but still has the pipes running through the center of the car (can't see them too well in this pic unless you look for them in the darker area of the photo), but he was smart and mounted some extremely thin mufflers along the outside of the underside of the trunk (or as I call it... the pit... because it is very, very deep for a trunk). So he only has about 3 inches less ground clearance instead of 4 or 5 inches like the guy above.
An idea that works even better (in my opinion) is to go alongside the passenger side of the car (like the stock exhaust plumbing), go over the axle with both pipes where the stock plumbing does, put a dual inlet/dual outlet muffler (same size as stock or likely smaller to accommodate the extra pipe that will take up space there) where the stock muffler normally goes, and then run two exits on the driver's side, or do what this guy below did. This way you don't sacrifice but maybe an inch or two of ground clearance in certain areas if any at all!
All three of the above applications have 1 thing in common: they are all illegal modifications. They won't pass inspection, because they took off the catalytic converters, they don't have O2 sensor(s), and besides that, it's illegal to change the location of the cats, which is why most aftermarket exhausts are cat-backs. I want my car to pass emissions without a single issue, so there's no way I would do exactly what these guys did.
My idea is to keep the stock Z28 exhaust manifolds and stock cats. Everything after that will be changed. Now here's the interesting part...
The Maserati Gran Turismo S has an extremely beautiful exhaust note. It is a nice humming sound at idle, and when revved, it releases a bark. Ex: http://www.youtube.com/watch?v=XuiH4zPCONU The way it apparently does this is through the use of a resonator mounted just after the cats and well before the mufflers. The mufflers are a very interesting shape and likely have something major to do with the sound as well, however, what is important here is that the resonator is what blends the combustion cycle into a nice even hum, and when revved, the gasses are moving too fast to be subdued by it. Camaros do not have a resonator. Mine will.
Gran Turismo (not S version) cats, resonator AKA central muffler according to Maserati, and plumbing:
Gran Turismo S mufflers AKA silencers according to Maserati:
I looked into it, and I can get the 'central muffler' which is actually a resonator combined with an x-pipe for about $538 online. Pricey. I can probably get it locally much cheaper (or even free?) from the Maserati dealership when they install aftermarket exhaust on a Gran Turismo or Gran Turismo S (which is sadly common, because then it no longer has the smooth idle, as the aftermarket does NOT use a resonator at all, just an X-pipe). It's #5 in the illustration, and about the length of a loaf of bread I would guess. Probably weighs around 15 pounds.