I have my new 70mm Fastman tb and AIRRAM cai. I need advice on what would be the best match up for the exhaust system.

I currently have the stock Dodge exhaust with dual tips and it sounds pretty good. But I want to match my exhaust with my intake capacity.

I would like new headers, cat, muffler, and pipe. How do you calculate back pressure and how much do you need. I know that they "tune" the exhaust so I dont want to play a sour note (insert cheap laugh track here..LOL) with the wrong setup. I want performance over noise but a nice low growl is always impressive.

Any suggestions are appreciated.

 

First you might want to see how much your engine can flow. A friend of mine put a CAI and header and really high flow exhaust on his Eclipse and it caused it to be slower than a stock Eclipse, and that was $2,000 worth of mods just to go slower. You need a balance between volume and velocity. Too much in and out and you will have a pig.

 

That is my fear. I hear that a certain amount of backpressure is good, but how do you know what that is?

I dont want to degrade my performance/fuel economy by picking the wrong parts..so what do you do?

 

Backpressure helps torque, but hurts horsepower. Almost every time you have to give up some of one to gain some of the other. The smaller the engine, the more important backpressure is. V8's don't need much backpressure, but 4 cylinders do. There are mathematical formulas to figure out the optimal size, but it cannot factor in the mufflers, converters, bends, etc. Your best bet is to find out what works best for others with a set up similar to what you have. You basically make an educated guess. You need to find out how many CFM the throttle body, intake, heads, exhaust manifolds/headers and exhaust flow. This is a rather complicated thing to do, so just find out what others have done and what has or hasn't worked for them. Generally, a set of headers, high flow cat and cat-back exhaust do wonders, but like the new Hemi's, some of these mods seem to lessen performance. You will also need/want a computer that takes advantage of these mods as well for maximum benefits.