I got started on my aluminum muffler build, but just barely. Leafy you weren't a kidding those perforated cores are a pain in the ****, although now I can make them in 15 min.

Little roller rig I built.



Finished product:




This core is 24" long, which is huge for a muffler, might end up getting cut down a bit depending on how the clearancing effort goes.

More to come.

 

I stopped using aluminum core even on aluminum ones with aluminum pipes. I just use purchased stainless cores and on the aluminum ones I just float the core on both ends. The aluminum cores just break even if they're floated, I think they just get too hot locally and blow out, even on an auto-x car on e85.

 

Well ****.......guess I can replace them quickly now. What thickness did you use if you don't mind me asking?

 

Like .065 I think.

 

Ahh, ok, this is .125" so maybe it'll last 2 laps instead of only 1.

 

So against my better judgement I went ahead with the all aluminum muffler build. I added a center gusset that'll get tack welded to the case after it's put together.


I decided to give mineral wool insulation a try.....50$ buys enough for 25 mufflers . It's rated not to melt at 2000 deg.


Stuff it in a box and welder up.


Money shot......


8.8 lb's for 4x12x20 muffler, The comparable magnaflow 14578 at 5x11x22 weights in at 23 lb's from what I'm seeing online (haven't weighed one myself). I'll take a 15 lb. weight savings any day.

 

Oh, non-reackable? yeah that aluminum core should hold up fine. I always make them so you can repack them because they get less effective after a few seasons, at least with the spec 31 or the burns packing.

 

This is my first time seeing this thread, but perfect timing. I've been thinking of making my own muffler lately. Thanks everyone for posting pics and info. Makes me wanna go build one now.

 

Yeah, this packing may not hold up in which case me and an angle grinder will will be spending a lot of time together. I could have cut the weight in half with thinner materials and a much smaller case. End plates are .125", perf. tube is .125 and the skin is .065". I think the beefiness is a good trade off for the weight.

 

I ran a full aluminium exhaust with vibrant muffler for 3 or so events. The problem with my motor is the overlap on the cams causing massive pressure waves at around 4000rpm which tore apart the perforations in the muffler and all the packing blew out. The whole exhaust was super light though so it's definitely something I'll try again when level up my ally welding skillz.

I like the idea of sleeving the inside with perforated SS but keep the rest of the exhaust and muffler as aluminium.

 

Well done Bronson!

I created a two muffler system to deal with sound. I used a stainless packed 17" long 4.5" diameter tucked up beside the PPF near the header. This takes the brunt of the heat and a good chunk of noise. I then added a fiberglass packed 15" long 4.5" diameter just before the diff with exit pointing down. This grabs the higher frequency sounds and is further back thus more protected from temp. Both are re-packable if need be. This design leaves the door open for flat panel undertray.

 

You caught me 😀, that's in the long term hopper.

 

I have been wanting to build an aluminum muffler for a while now. This site sells 7" OD 16 gauge aluminum tube which was my plan for the body: Aluminum Intake Tubing 7" OD

I'm curious to see what you do with the hangers.

 

Double post

 

Finally wrangled enough time to finish this up. I had to add 18" worth of stainless tube and a flex joint to my down pipe. This section will get a shell of a cat to pass visual inspection. That added 5lbs to what ended up being a very light setup at 14.5 lbs.




we'll see if those screws pull out of the case over time.

 

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Yeah yeah, booger welds......

 

Where's vlad to make fun of your cheater bends?

 

Believe it or not those are mandrel bends, just cut what little bend I needed from the 90's and used the strait leg since I was short on strait pieces.

 

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