2.5" exhaust to 2.25" muffler

[CorvallisBMW]

I currently have a 2.5" single pipe on my m30 swap. I really dislike my current Dynomax muffler and want to upgrade to one of the stainless Magnaflow muffflers such as the 14815. However they are only available with a 2.25" inlet. Anyone out there know if this will cause too much backpressure in a bigger motor like the m30? And advice/tips/experience is appreciated!

[nando]

why? 2.5" is already the same overall size as stock. 2.25" is smaller. the only thing the 14815 has going for it is nice tips..

[ak-]

I currently have a 2.5" single pipe on my m30 swap. I really dislike my current Dynomax muffler and want to upgrade to one of the stainless Magnaflow muffflers such as the 14815. However they are only available with a 2.25" inlet. Anyone out there know if this will cause too much backpressure in a bigger motor like the m30? And advice/tips/experience is appreciated!

The 14816 has a 2.5 inlet.

[CorvallisBMW]

why? 2.5" is already the same overall size as stock. 2.25" is smaller. the only thing the 14815 has going for it is nice tips..

Can you think of another muffler with a similar sound and 2.5" inlets? I'm not concerned about the tips, I just like the way that model sounds.

The 14816 has a 2.5 inlet.

nope, 2.25"

http://www.summitracing.com/parts/MPE-14816/

[FredK]

It sounds like raspy garbage.

[Wishno87]

I think we are mixing up numbers. Darin you mention a 14815 but your link is a 14816. I have a 14815 and I'm pretty sure its a 2.5.

[CorvallisBMW]

I think we are mixing up numbers. Darin you mention a 14815 but your link is a 14816. I have a 14815 and I'm pretty sure its a 2.5.

2.25"

http://www.summitracing.com/parts/MPE-14815/

All magnaflow's mufflers from that series, no matter the tip style, are 2.25"

I'm looking for something with a similar muted growl, something nice and beefy but not raspy or tin-y. I've heard lots of Magnafows, like them a lot, but haven't been able to find anything in a 2.5" that sounds similar.

Hence my original question.

[Wishno87]

Excellent correction. Although it does get a little droney sometimes I do love the sound of my 14815.

[nando]

check out the mufflers from vibrant

[CorvallisBMW]

check out the mufflers from vibrant

hmmm maybe something like this?
http://www.sfxperformance.com/parts/VIB10513.htm
I've never heard of Vibrant before

[MR 325]

check out the mufflers from vibrant

Exactly what I was going to say. I have never personally used their stuff but everything I've heard with one of their mufflers sounded excellent!

Don't do the 2.25" downgrade.

[immajackuup]

megan moe muffler 2.5 in and out.

[e30trooper]

Exactly what I was going to say. I have never personally used their stuff but everything I've heard with one of their mufflers sounded excellent!

Don't do the 2.25" downgrade.

what about a m20?

[nando]

2.25" is still smaller than stock for an M20

[CorvallisBMW]

I went ahead and ordered that 2.5" version, we'll see how it sounds.