: Dual Outlet Exhaust

DopeStar 156
03-23-07, 03:02 PM
I was thinking about replacing my muffler with one of these.....

http://cgi.ebay.com/ebaymotors/Flowmaster-40-Muffler-3-Inlet-Dual-2-5-Outlet-430402_W0QQcmdZViewItemQQcategoryZ33636QQitemZ1700 93096717QQrdZ1QQsspagenameZWDVW

Then following through with a dual outlet system. I was also conceptualizing......

This configuration would be the easiest to install because I'd need less piping.

This configuration is what I'd prefer and would require more pipe to reach the other side of the rear.

What sizes do I need to know for purchasing the dual outlet muffler and what else would I need to know for installation?

03-23-07, 04:15 PM
The top one looks like a ricer. If your going to spend the bucks, go with a true dual system. A good cat back system done by a pro should not cost more than $300. Oops, just saw the New Jersey license plate and therefore the cost could be more.

DopeStar 156
03-24-07, 12:18 AM
What does an NJ plate have to do with anything?

03-24-07, 06:14 AM
I assume you live there. My cost estimation was based on where I live.

DopeStar 156
03-25-07, 08:10 PM
I put my new tires on today and while I was under the car I had a look around. Apparently a muffler with dual outlets would be no trouble at all to install. There's plenty of room for a second pipe to cross over to the driver's side.

03-25-07, 08:56 PM
For duals just look at how they did it on the 94-96 FWB. Basically the same chassis right.

03-25-07, 09:19 PM
Don't you need to get a crossmember from a Caprice or newer Fleetwood to run duals?

04-06-07, 10:23 PM
You could probably do it for $300. Not sure if you do or don't need a cross member.


04-08-07, 08:47 PM
There is plenty of room to do duals down one side with dual cats with the 307.

BUT, it is illegal to replace or remove a GOOD catalytic. And it is illegal to change the OEM configuration or location of the cat.

So cat back is 100% legal if that is an issue. But dual cats properly fit can fit both on one side (look at a 96-99 Suburban 350 or 454, you would be amazed how tight it is). The farther the cats are from the engine you will need heated O2 if emissions are an issue. It can't hurt anyway.

Keeping the stock crossmember and both cats on one side, dual 2.5" pipes is about max. Dual 2" is probably all that is needed. Dual 2.25" would be ideal for most anything, and a boost to hp and mpg.

DopeStar 156
04-09-07, 01:10 AM
No problem, I'll just swing kick my catalytic converter. Uh oh, looks like it needs replacing......