Anyone have any engineering feedback or thoughts on how effective the dual exhausts are that basically run a single pipe into an apparent 90 degree split to dual exhaust from a muffler?

I always assumed the straightest path is the best, and at least for my SRT-4 most designs have more of a y-shape split, with or without mufflers at the end, but usually don't dump straight into a canister and then do a 90-degree turn in each direction.

I notice the Cobb and ETS systems have the straight, then 90-degree split design. Agency Power and Buschur appear to have more of a gentle y-sloped rear split.

I wonder if the y-designs flow better? The design of intercooler end tanks always seems to be important for airflow characteristics, so why would that not apply to exhaust flow as well?

Thoughts?

 

Pics of the examples I'm talking about.

Buschur's y-design


ETS 90-degree muffler (not a sharp 90, but certainly a harder turn than Buschur)

 

Hmm, no comments? I guess exhaust is all about girth...

 

^^ That's what she said!

I would think the split Y design would flow better, but it's probably a trade-off of sorts.. maybe noise reduction having 2 mini-mufflers vs only 1, or maybe ETS didn't want a muffler that close to the driveshaft?

Specialty-X has a very nice split Y dual exhaust with dual mufflers, but originally, they were angled down too low and caused ground clearance issues.. plus it's possible that having the mufflers outside of their intended mounting point would effect underbody aerodynamics a bit.

Dunno. Interesting question, though.. I'm guessing a single exit straight pipe would probably flow the freest, but would also be the loudest.