Just wondering if any of the experienced guys had an opinon on this. Right now Im running 3" duals with an x pipe dumping before the axle. I love the system and it sounds great but it does leave me much choice as far as a serious chassis mount torque arm goes. In light of this I have been thinking about going with a 4" mufflex system.

At my power level is there a high enough HP and TQ advantage provided by the duals over a 4" system? Then there is the weight difference...

Ive seen the numbers posted by Chuck but arent there ALOT of fast guys using the 4" system?

 

A good rule of thumb is that a 2.5" dual set up = 3.5" cat back system.
A 3" dual system = 4" cat back system.

I would stay with your current set up since you dont have the bends that a 4" cat back has plus like you said there is the weight difference between the duals and the Mufflex system. I think you're running the right set up as you have it right now.

 

realize there is only an 11% decrease in volume going from dual 3" to single 4" pipe. however another thing to consider is the physics behind the flow of a fluid (this case air/exhaust) through a tube. there is a certain amount of restriction caused by the sides of the tubing. since there is a 33% increase in surface area of the inside of the dual 3" tubing compared to single 4"...that could more than offset the decrease in flow volume.

just some physics to think about. i honestly don't think going to a 4" system will negatively affect your setup much if any

 

What kind of torque arm are you looking at?

 

Id like to get a chassis mount torque arm. Most likely something custom but along the lines of a spohn or BMR trac pack.

I never thought about the restriction just by having more pipe..hmm. Intresting.

 

There's always this option:
http://www.ls1camaro.net/freehosting/dsc00734.jpg

 

There's another part of the this that probably matters more than "flow area" and that is average exhaust velocity. Since scavenging efficiency is proportional to velocity, that's gotta account for something.

If you look at it from the engine up to the y-pipe it's all the same. From there you either have a large volume pipe (slower velocities from there back) or you have a system with an x-pipe. With the x-pipe you get the "balancing effect" and you maintain gas velocities.

If I had to choose between a dual exhaust (no crossover) and a y-pipe, I might go with the y-pipe but if an x-pipe were in the choices, I'd go with the x-pipe. I think it's the best compromise.

-Mindgame

 

A real world example....

George Baxter's 30th SS convertible was pushing 1,125HP through:
-Hooker LT's
-custom Mufflex 3" Y-pipe
-Mufflex 4"/Flowmaster muffler catback
-"2OTL" tips

The car was dyno'd.

He removed the exhaust system, leaving simply:
-Hooker LT's
-A 3" Borla XR1 on each collector
-A 90-deg turndown on each Borla

There was no change in RWHP. The 50# weight savings from the exhaust (and a few extra #'s from other minor changes) did help the 3,900# car drop from 9.teens to 9.05@155mph.

 

There is a comparison in this thread based around a street build. Lots of opinions on the subject both ways too.

http://web.camaross.com/forums/showt...ghlight=x-pipe

-Mindgame

 

I have a mufflex cat back for sale if your interested.

 

Thanks for the info Mindgame and Injuneer. Looks like either will be plenty for where I am at now.

Maybe I can fanagle something like Birdie2000 posted and keep the duals.