id love to but no use haha



and to the rest of you, good point on the 4" muffler then branch out, however I can't fit 3" I'll get some measurements tonight on what I can fit, it's tight I know that, so I'm going to have to wrap the exhaust since it's going to be within 1/2" of frame and inner fender (paint and powdercoat)

 

I have exactly 2.5" in between the two areas I have

 

GMracer- you can oval out the pipe if need be. Take a 4" and just oval it out where you need the tight fit

 

If im understanding it, He wants the 2 inch for fitment purposes and sound after the 4 inch, and he will have a cut out that can be opened to allow the 402 to breath when he needs to get on it.

Right?

But i agree, 2 inch is tiny, 2.5 would be better IMO

Dustin

 

would there be an issue taking 2.5" and ovaling it out?

 

Im sure it would work. Plus its not like your looking for the actual flow quality after the cut-out haha.

Dustin

 

cross sections-wise
pi*r*r=A

2.5" circular
pi*1.25*1.25=4.9087in^2

2.5" flattened to 2" (assuming its now 2"X3")
pi*1*1.5=4.7123in^2

4.7123/4.9087=~96%

So 96% of the flow capacity is still remaining if it indeed smashes to form a 2x3 cross-section.

 

You know with the caliber of truck you're building, ovaling the pipe yourself would look pretty shitty IMO. It will probably draw attention since it'll stick out next to an otherwise smooth under carriage. Go with the actual oval pipe. They have transitions from oval to round that don't affect flow, and the flow area of the pipe itself won't be affected. They also have mandrel bends in both directions of the oval. You might be able to squeeze dual 3" too which won't hinder flow coming from a single 4" like dual 2.5's will...check it out:

https://www.drgas.net/catalog.php?catid=3

 

Whatever you do don't get tips that are in the shape of a bowtie!
I'm just gonna re-iterate what bill said in post #7, for flow purposes stick with a single.

 

thanks man I appreciate that, should be good enough. Since I love a loud truck anyway.
Thanks for the link I didn't really plan on doing it myself, I just worded it that way.

Check my build, you'll see where I'm going with it.