I was thinking about getting a mandrel bent 2.25" muffler back pipe bent soon. why? because the 2.5" bend over the rear diff is really crappy for air flow it seems.
and from what iv read 2.5" takes a bit away from low end wich i like to use a lot. and 2.25 takes a bit away from the current high end i have because of 2.5" catback. so i can find an even medium with this, right?

 

2 1/4 is fine

 

any recomendations on pipe bend ideas for the muffler back? most efficiant exit point?

 

I just cut mine off right behind the axle like so:
click to enlarge

 

whats at the end of your pipe?

 

looks like he has a supertrapp muffler on there.... or some sort of diffuser

my muffler jsut has a turndown and exits before the rear axle, however i have a pickup truck and that is legal for a pickup, it isnt legal on a 4runner, but many people do it that way also

 

i was thinkin bout that.. iv seen some desert runner fords like that.... what kidn of imporvement do you see?

 

Yeah thats my SuperTrapp disc only muffler, it's tunable and freakin sweet. I eventually plan to go with the full SuperTrapp muffler, not just the disc one. The SuperTrapp is great I can give it more air flow (by adding more discs) and improve the high end or add back pressure (by removing discs) to help the low end. Granted it's not going to be a HUGE difference in power but it is noticable.