Looking at the Dynomax website, I find that they have a system to rate the horsepower limit on their mufflers. They call it the "Powertech Index." I studied that and then found their pdf file that shows the specs on their race mufflers. They rate all their 3"ID mufflers that use a straight pipe through the muffler to be sufficient for over 450hp. I say 450 because they seem to quit counting there.
My question is: Wouldn't the rest of the 3" exhaust pipes be able to handle the same horsepower or more than the muffler? Most on this board put a limit on 3" cat-back or no cat systems at around 300-325hp. Are the bends that limiting on horsepower?

 

So they're saying a 3" I pipe is good up to 450hp?? Seems a little restrictive on such a motor to me.

 

Here is the 'powertech index' and a list of their mufflers.

http://www.dynomax.com/documents/race_specs.pdf

3" straight through mufflers have a single index rating of 1000. 1000/2.2= 454.5 hp. Am I doing this right?

Can their mufflers be less restrictive than the rest of the pipes?

 

That much horse? Go with just headers! Or some dumps. How about some 1 chamber mufflers?

 

I am not looking for suggestions on a system to handle 450hp.

I wondering what to think here. People on this board have said many times over that a single 3" won't allow an engine to produce that kind of power and yet Dynomax is providing some published evidence (as far as I can tell) that it could.

Dynomax also lists a 3" that does not look to be a straight through design and it is only good for 155hp. Another has a 3" on one side (I'm guessing inlet) and two 2.5 on the other side that is good for 290hp.

Are the doubters using inferior flow systems that use poor components or is Dynomax risking their reputation on their claims?

 

There are people on here making more than 300 horse on 3" pipe, but I would think that after you get much above that you could probably gain quite a bit by going with better exhaust.

Ben

 

thats exactly it, you can run single on any high end system but you will be losing power. if you want an easy dual exhaust setup, get long tube headers, put car chemistry inserts in em and run 2 1/2" pipes back as far as you can hugging the underside of the car