The two pipes actually merge nicely into the 3” section. There are separate 2.25” until they reach the 3” part and by this point, they are exiting the 3” tube. This is no different then any merge collector.

I may have misunderstood the routing. For a 911 I guess the two Flow Out ports will become Flow In.

They quote 2.5" on the two top and 3" on the bottom (this is stated as would be used on our dual side entry setups). And if you just read that without seeing these pictures you'd think it's perfect. But looking at those pics it's like not even close to the rendering image of the cutaway and it is t truly 2.5" since it shrings down to 2.25" right before the muffler body. It's like bait and switch!
Did you order the version with the 3" outlet(or inlet if you own a Camaro)?

It’s definitely not 2.5 inside the muffler, it’s only that on the lower two inlets. The outlets is 3” and layout is like the rendering shows. Honestly, I don’t see any wrong with my SSI and the 2.25 actual size. We’ll see once I get some additional tubing. Anyone have a source for stainless SSI flanges? I waterjet some mild steel before, but wouldn’t mind stainless.

I sourced mine on amazon. pretty wide selections there and on ebay too.

This Borla looks very similar internally to my beloved Dynomax 17676 single in/out that I had on my original heat exchangers, but adds and inlet for my current B&B header situation. Following with extreme interest.

Have you gotten that muffler mounted up yet?
My BBE muffler is like breathing through a towel...and heavy as the Earth.
My home-built 2->1 is just a little loud. I'm still trying to find that ideal setup and this one looks like it may be in the ballpark.

Anxiously waiting for an update on the Borla. In the meantime, I spent $70 at Speedway Motors and bought materials to make a pair of Megaphones (evil laugh.)

OK, so I bolted this muffler on my car. I believe it is an M&K. I took it off after about 5 miles. The drone hurt my ears.

The pluses, light weight, nice quality welds and stainless. Power seemed fine and I could not tell any difference on my butt dyno compared to my Dansk sport.
http://forums.pelicanparts.com/uploa...1654565814.jpg
I'm kicking myself for not taking a video.

Bummer
the welds they do are pretty neat aren't they. Are they all made in USA or outsourced to China?

That muffler is NOT an M&K.
It does look like our dual inlet street version prototype but that muffler was never sold.
There is a knock off being produced by a couple of entities now.
> All M&K mufflers have removable tailpipes (minus the M33 or custom), those are welded on.
> All M&K mufflers have a straight shell, that one has angles on the ends.
> All M&K dual inlet mufflers have a reinforced crush section in the back facing the engine console.
> ALL M&K mufflers have always been and will always be made in the USA by master fabricators and welders.

I was waiting for Brian to reply and found that I’m pretty good at identifying his mufflers by appearance.

Thanks for setting the record straight. I should have said I was "told" it was an M&K, obviously not.

Looks like a Monty Muffler.

No similarity at all: Monty Mufflers | Mufflers for Porsches

Just to clarify, the removable tailpipes is a relatively new feature…?

I’ve had two M&K sport exhausts with welded pipes:

M27 purchased new in January of 2021
M29 purchased used but originally from roughly 2019

I changed the straight tailpipes to bolt-on several years ago which allows for easy to do tailpipe options.
M27 dual in single out sport muffler has had clamp-on tailpipes for at least 15 years. Are you sure this is not an M33 (single inlet)? The M33 is the only 911 muffler in our lineup that has a welded tailpipe.
M29 S muffler could have had weld-on tailpipes in '19 as that was an option. There are custom mufflers as well but the one pictured above is not one of them. The angled ends were never a production item for the 911. A picture of the back would also be very telling.

Borla? Borla? any updates?

Mine is with the exhaust fab guy. Should be done in a couple weeks.

That is a muffler I built for Ben to use up the inventory of the 3 part shell design. The welds and quality are the same as m&k.