There are headers available for these engines, but they do not seem to show a performance gain large enough to justify them on turbo charged engines. In order to fit them, they are constructed of fairly thin material and don't last very long.
If you are going to a large exhaust system, then you might consider
upgrading the flex joint to better match the new exhaust pipe size.
A 2 1/2" down pipe is usually sufficient, even if the rest of the exhaust
system is 3". Such fabrication is usually complicated and expensive.
If you are upgrading the turbo, then chances are it will accommodate a
2 1/2" downpipe with no trouble.
A less expensive alternative is to install a cat-back system.
Here a larger diameter pipe, equivalent to or greater than your downpipe,
is installed right on the stock catalytic converter. Keep in mind
that the stock catalytic converter is quite restrictive, so a high flow
replacement would be a good idea.
There are quite a few options available for catalytic converters (or "cats"). If your state does not inspect and look for a cat, then you can probably make due without one. These engines, when properly tuned, can usually pass emissions without a cat. The stock cat has a lot of restriction, so it is best to get rid of it. A way to make the inspectors happy is to cut the cat open and gut the catalyst out. If your engine can pass without the catalyst, then you might consider this. Probably the best option for most is a high-flow cat. These are available for anywhere between $50 and $100 and are street legal.
To increase performance at the track, cut the exhaust pipe about six
inches on both side of the cat and either have flanges welded on with stainless
steel bolts, or use stainless steel sleeve clamps to mount it back up.
Another way is to install a dump valve near the down pipe. These
can be the cable-operated type, or the bolt-on cover type. This way,
you can remove the restriction of the system while at the track.
The next option is a straight-through muffler design, such as the Dynomax Race Magnum or Borla Sportsman. These offer zero restriction because the gasses pass straight through. They work by absorbing some of the pressure waves in the exhaust stream into a fiberglass pad that surrounds it. They aren't all that effective on turbo engines because a lot of the energy in the waves is already absorbed by the turbocharger, but they will take the edge off of a noisy exhaust.
Another option is a high-flow baffled muffler such as the Flowmaster. There is a small amount of restriction because the gasses have to pass through a series of baffles that are designed to reflect the pressure waves so that they cancel each other out. These mufflers are more effective than the straight-though type, and are a better choice for street performance. They don't work the same way as conventional mufflers, which use diffusers and chambers to stop the pressure waves, so they don't create nearly as much back pressure.
Probably the best choice for street performance is a high-flow version of a conventional chambered or "path" muffler. They do have more restriction than any of the above, but still flow much better than the stock unit. The most popular muffler of this type is the Dynomax Super Turbo. These have two chambers with three tubes, but the tubes are perforated to further reduce restriction. There are also many other brands that make similar mufflers, but beware of some of the cheaper units. Some to not maintain the inlet and outlet tube diameters inside the muffler (usually 3" mufflers, which only get 2.5" internal tubes). Others, while aluminized on the outside, are just raw steel on the inside. The internal tubes and baffled rust out quickly and the muffler "blows out". Dynomax Super Turbo mufflers have arc-welded internal parts and are fully aluminized and padded with fiberglass. Since the Dynomax Super Turbo is one of the most popular mufflers used, here are the Dynomax part numbers that fit well on these Chrysler FWD vehicles.
17741: for 2.25" exhaust pipe, round, 6" diameter, 14" long, 2.25" legs, with OEM hanger mount
17708: for 2" exhaust pipe, round, 7" diameter, 18" long, 3" legs
17709: for 2.25" exhaust pipe, round, 7" diameter, 18" long, 3" legs
17710: for 2.5" exhaust pipe, round, 7" diameter, 18" long, 3" legs
17698: for 3" exhaust pipe, round, 8.375" diameter, 18" long, 3" legs
Avoid diffuser disc type mufflers such as the Supertrapp. They basically work the same way as conventional mufflers: by diffusing the exhaust at a steady rate to contain the pressure waves. In order to do this, they have to produce some back pressure. The more discs you add, the more the muffler flows, but the louder it gets. Creating back pressure at the muffler defeats the whole purpose of having the larger exhaust system.
You can always add an exhaust cutout to your system for use at the track.
One way is to cut a section of pipe out near the down pipe and either have
flanges welded on with stainless steel bolts, or use stainless steel sleeve
clamps. Another way is to cut out a hole in the pipe near the down
pipe and cover it with a sleeve clamp when not at the track. Another
way is to install a dump valve near the down pipe. These can be the
cable-operated type, or the bolt-on cover type.
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This page is maintained by Russell W. Knize and was last updated 06/11/99. Comments? Questions? Email email@example.com.
Copyright © 1996-2003 Russ W. Knize