Among a ton of other mods, I am installing a set of 3/4 length L&L headers on my 460. I am thinking about going with a 3" single exhaust to save space instead of the 2.5" true duals. Good or bad idea? The motor for now is basically stock... Performer RPM manifold, 750 carb, mild cam, straight up timing, mildly ported D3s. I plan to build up another 460 around 500hp 600tq in a year or so, it would be nice not to have to do the exhaust more than once. Any and all suggestions are appreciated, thanks in advance.
John

 

I would do dual exhaust if you plan on upgrading in the future.

 

2.5 dual with a crossover pipe about 16-18" behind the header flange

 

They going all the way to the rear of the truck?

on mine im running the 2"/3.5" Maddog headers fenderwell exits and that goes into 3" Pipe into a single stage Flow-master and dumps just behind the Cab.... sounds real good.... to me anyways

 

Is dual 2.5 enough for a mild 460?? I ran 2.5 duals into a single muffler/tail on my 302s and 351w. Dual 3s on the 351M.

After I get done moving, I'm doing a motor for the van, trying to decide on what to run under it. I have some 3 in/out mufflers, so I could run duals, or do a two into one, but would run like a 3.5 or 4 inch tail if I did a single. C

 

I ran dual 2.5s on my first three 460s and my h-pipe is now under Pauls b-hoe.

 

Just a note that have taken note of when configuring my exhaust, unless you like toasty floor boards, right under the cab is not the best place for a muffler. Hindsight generally is 20-20.

 

Follow link to exhaust diameter guide:
Magnaflow Technology

Duals and x pipe is best

 

When I was running the factory 460 manifolds I had 2.5" true duals with 40 series Flowmasters. It sounded really nice, not as loud as I would have liked but you knew it was running. I have been debating on just hooking it back up how it was, but with headers. Another option I have is a Dynomax Ultraflo dual in/dual out X-pipe muffler, I'm not sure if it will fit because of the length and the short wheel base of the Bronco. I want to make some noise but not be abnoxiously loud. Any thoughts?
John

 

2.5" exhaust should be good for 5000rpm and down, low end torque and mid range very strong and decent top end. if turning harder around 4000rpm to 6500 a lot go 3". i run this application in my 472" bbf, solid cam ported flowed 475 to 500 hrspwr. if auto what stall converter? have ran other set ups with bigger stall converters and headers and exhaust will change as needed per rpms and weight.