Thread: 3" Exhaust Question

ok, i have a 3" mandrel bend exhaust on my car. 3" straight from collector on header, straight through 3" resonator, 3" straight through muffler pan.

I think my muffler pan is too loud and want to get one from a guy who carries them from japan.

japanese specs are bit different so I will either get 70mm (2.75") or 80mm (3.14")

the the 80mm would have been ideal but the pan may not fit under car.

question: if i go 70mm (2.75), will i lose power seeing the rest of exhaust is 3"? they say the flow is as good as the smallest diameter on the exhaust.

plz bear in mind that i cannot afford to lose even as much as 0.5hp.

thanks for your comments

peace

If it is sound your trying to dampen just improve your resonator i have on a Magnaflow 36" long resonator which is a pain to tuck under a sentra but the sound is super quite some people weld two resonators together

Check this link out
HOW TO: Build a (Quiet & Inexpensive) 3" Side Exit Exhaust - SR20 Forum

actually, i have a 24x6" magnaflow resonator and not sure could fi a 36" ones. the car si n15 not b13. think the actual resonator section is 18". i probably could have gone with a bigger magnaflow pan. the one i have is 8x5

but yo didnt comment on the 2.75" pan? but i get that you are thinking it may rob power.

peace

rather add an additional muffler or a resonator or even a decat muffler in 3".

80mm should be outer diameter.

About loss/gain. With smaller exhaust you gain in lower rpm, with bigger exhaust in higher rpm... there is still loss/gain.

Totally but its not very pronounced if you tune for a 3" exhaust but I think 70mm would be plenty and the sound would be more tolerable. I had a 3" on my dd and would have liked it to be quieter and that was with large muffler, resonator and a high flow cat.

cool

i will look into the option of adding another resonator. dont have much space though

peace

I *think* adding another resonator will take the 0.5HP (or more) that you do not wanna lose.

Maybe the 70mm will not make you lose anything, but cant tell until you try. With the 80mm, as you well put it, the exhaust will continue to be as the smaller choke = 3 INCHES and if it helps with the sound...

i used straight through resonator still, so it would not be a problem.

will have to look into the muffler pan options some more as there is not space for next resonator - maybe remove and replace with a longer one.

hope to find a 80mm muffler that will be able to fit under the car

thanks guys, for your input

peace