Diff between Cat-Axel Back Exhaust

[KaMaKaZiPyRo]

Whats the difference???

[crxlvr]

a cat back is an exhuast that is replaced from the catalytic convertor back, an axel back is just the rear section where the muffler and tip are, no piping in between.

[KaMaKaZiPyRo]

so since the cat back has a muffler and all the stuff an axel back has, why do people buy that? they cost about the same 400-700

[jajimo]

They shouldn't cost the same.

Axle Back:
One peice, comes with muffler, tip, and a short pipe.

Cat Back:
Two peice, comes with muffler, tip, that same short pipe, plus the *B-Pipe* which is the mid-section of your exhaust. Most also include a resonator (or atleast a resonator-shaped peice of pipe).

That B-pipe can be very important. When I purchased my first exhaust, it was supposed to be a "cat-back" but they only gave me an axle-back, and I didn't know the difference. Well, the reason I was replacing my exhaust in the first place was because both the muffler and B-pipe had rusted holes in them, so it sounded like shit. Since I only got an "axle-back," the stock b-pipe was still leaking exhaust, causing it to be loud and annoying. Still, since I didn't know the difference, I paid $300 for this. It should have only cost me less than $200.

When I bought my second exhaust, it was actually a "cat-back" and cost me $484, although that was a good deal because they retail for $649. Take into consideration this is one of the best exhausts on the market, however, so that accounts for the huge price tag. Still, cat-backs and axle-backs should not cost the same. In fact, axle-backs should be pretty hard to find since they do nothing for performance (your stock b-pipe is still bogging you down) and if you're going to spend money on a new exhaust, you might as well go for more than just a muffler + a short pipe attached.



Notice there are lots of different pieces to your exhaust system. The axle-back peice is the peice with the muffler attached. The b-pipe is the longest part of your exhaust sytem, and is the one with the 2 90-degree turns (although a performance exhaust should have a straighter pipe).

The main peices of your exhaust go:
Exhaust Manifold
Down Pipe
A-Pipe (I believe, some may not have an A-Pipe at all)
Catalytic Converter
B-Pipe (usually includes Resonator)
Rear-Section Pipe (attached to Muffler)
Muffler

[SiGNAL748]

They do sometimes cost the same, depending on brand and application.

For example,

http://www.optauto.com/webstore/prod...=yes&dept=1214

Then again, we all own measly hondas anyway, so we don't usually come across axlebacks this expensive

[Ricochet]

Even worse: JDM shit y0!

[KaMaKaZiPyRo]

damn $680! i wonder how much the cat is..

[eckoman_pdx]

KaMaKaZiPyRo, your question has already been answered to a certain extent, but I still thought I'd add a few things seeing as you where pretty confused as to nature of how exhaust systems work and the concept of what each does.

Now as jajimo already explain, the exhaust system is comprised of the exhuast manifold (known as a header on the aftermarket), the downpipe (this is basically the lower peice in a 2-peice header, or the pipe that runs from the exhaust side housing on a turbo down to the cat), the cataylic convertor, the exhaust piping and the muffler.

A cat-back replaces the exhuast sytem from the cat-back, all the piping from the cataylitic convertor back, the muffler, all...as has been explained...axel back is just that, the little pipe, muffler and tip from the axel back. The big difference here is just that...piping.

Now this makes a huge difference for one reason. The muffler isn't what is giving you the little extra power, it's the piping for the most part. If you have a 92-95 civic, for example, you have 1 3/4" piping...very restrictive. A normal cat-back system will replace all this with 2 1/4" piping. Basically, the new "cat-back" system has been designed to have better air flow and better scvanging, therby increasing power output a bit. This can be thought of as modifying the exhuast system for perform, much like when you by a qaulity header (the exhuast manifold). It's the same principle with this as the header, the air flows better though it and the effects of scavenging are increased, which results in better airflow, which is more power.

Now the axel-back does not of this. This of it as a bolt on unviersal muffler for your car. It's basically just a short pipe that bolts to the exhuast section in between the axel and the bumper. This is basically ment as a way to just bolt a new muffler onto the car, versus welding a universal one one. There isn't really much performance gain. The piping on a 92-95 civic in this example would still be 1 3/4, restrictive and stock. The little bit of piping from the axel back and the muffler won't do much for performace, the rest of the piping has not changed. It's basically just a visual add on at this point, in comparison.

Since it's the piping that really helps increase the power, and the piping hasn't changed with an axel-back, you can how an axel back is similer to a universal muffler in the fact it in by itself is more of a visaul add on piece than a performance piece, it changes the sound more than the performance. A Cat-back exhuast system, on the other hand changes out the whole exhaust system from the cat-back. This increases power output (levels vary depending on many things, such as design). The main difference is basically one (axel-back) is a more visual add-on, the other (cat-back) is more a performance add-on. A muffler by itself will not create any extra power, you need to proper piping to go along with it. This is something the axel-back inheriantly lacks by nature.