I have a 92 Camaro with a 358sbc that came out of an old dirt track race car. I don't know a lot of the specifics of the motor besides that its a Stenhouse motor with a bullet cam that I put in it. Its probably somewhere around the 350-420 hp range (never had it on a dyno). I have 2.5 inch true duals exiting in front of the rear tires with 12 inch Cherry Bomb glass packs, no cats, and Hedman shorty headers. I was wanting to know if went to a single 3 inch exhaust dual 2.5 exit with a Magnaflow muffler such as the #16829 system would that be a good set up (in terms of tubing diameter)?

 

From what i remember reading 2 years ago when i did my system (hooker headers w/y-pipe into 3" flowmaster catback 3" complete dual out) was that 2.5 crush bend is similar to 3" mandrel bend in terms of flow. Also that 3" mandrel bend is good up to any where from 350-450hp depending upon where you read it at. Seeing that you already estimating HP 350+ I think you prob want to go 3.5 single.

 

So your thinking a 3.5" single with dual out would be better for me than the 3"

 

Dual outlet ends up taking a snaking path through the muffler. Single outlet performs better. Both work fine for what you are doing but just letting you know which is actually better performer. Appearance is the tie breaker depending the look you want for your car.

 

 

I defiantly want dual outlet. I'm just not a big fan of the single outlet. I was mainly wondering if I need 3" inlet with dual 2.5" outlet, or something larger such as a 3.5" inlet with a dual 3" outlet (or whatever inlet/outlet combo would be best)

 

So if i went with the 3.5" inlet does that mean I would need dual 3" outlet?

 

Neither am i BUT do you really want Dual outlet for the look? Or do you just not want a single exhaust pipe showing? You could always have it dumped behind the rear bumper.

If not i would prob guess yeah if your assuming MIN 350hp your gonna want atleast 3.5" single. You just need to start searching for exhaust systems of 3.5" single. From what i remember reading/finding is that most of the systems are single out. Now im sure you could figure some way out (or someone already has) to throw dual outs on it, it just might not be setup that way "out of the box".

 

I want it for the look. I like the way these cars look with the 3" and 3.5" chrome tailpipes coming out the rear. I was planning on buying a muffler with the appropriate inlet and outlets instead of a out of the box system, because I have an exhaust guy that fab up almost anything.
Thanks for your input by the way

 

Yeah me too haha thats why i went with a 3" single with 3" dual out muffler, love that look!

Yeah then your set! On this page http://www.hawksmotorsports.com/82-9...haust-systems/ are a couple examples of some 3.5" single systems. There are a couple there with 3.5" dual outs but they are quite expensive!

No prob, just passing on the information that was once told to me! Its a TGO thing

 

i'd go 3 1/2" back to a 4" inlet muffler with dual 3 1/2-4" outlet. i agree the muffler will be the bottleneck. you could also check the cfm rating of your muffler and compare it to the cfm rating of 3 1/2" straight pipe. but everytime you introduce bends or mufflers, your lowering the cfm rating. having the muffler as far back as possible is a good thing too, because the exhaust gases will flow better the cooler they are, (less heat expansion).

heres a generalized STRAIGHT pipe cfm to HP chart.
http://www.exhaustvideos.com/faq/how...98809814453125

 

If you friend can fab anything he can fab a system like the Borla, 1 going thru the muffler and 1 straight pipe with restrictor, you can even pick the sound level you want.

 

 

It is opposite that. The velocity of compressible fluids, such as exhaust gas, slow as heat is lost from the system. Think of it as an energy trade-off. Heat is energy so if the system loses heat then that energy has to come from somewhere, and that somewhere is the kinetic energy (velocity). A practical application is exhaust wrap being used on race cars to improve exhaust velocity (and engine performance).

The muffler is at the back of the car for one reason and one reason only... noise. Point the exhaust tips out the back for the least amount of interior noise. Hidden turn down exhaust is very cool but there will be more noise in the cab.

 

Awesome i knew some other guys would hop in here. Thanks for the link!

 

What you really want is a 3.5" pipe back to the muffler and a 3.5" tailpipe out. But any decent shop can fab up a "fake outlet" on the side of the muffler where there is no actual pipe. I know Mufflex does this for customers for the "look".

 

Don't waste your time any money over thinking this exhaust stuff.

Go with what is a proven setup. I have cars putting down 429/430 to the rear wheels with
a dual cat 2 1/2" into a 3" catback Magnaflow muffler with dual outlets.
Or a GMMG exhaust on a 355 motor.

 

Dyno Don really knows his stuff... I really wish i had a set of his headers/y-pipe.....