Let's go muffler shopping for a weird hot rod

I'm compiling an expensive Summit Racing cart of exhaust components for a custom exhaust on the Rice Rod. 2JZ N/A inline six, with possibility of turbocharging in the future. I'm designing a lake-style header while it's N/A, with a capped dump that will be capped most of the time. It will have a branch that goes to 2.5" SS 304 tubing all the way back to a muffler. The future turbo version will obviously have a different header, but will also have dumps and normally be routed under the car through a muffler. I'm open-minded to sound and don't have any particular options in mind. I have a SS mid-pipe resonator that came off a Avalon, and it sounded pretty good with a V6, so that's obviously the easy button. But I might be saving that for a nother project.

So, I need a muffler and there are far too many options. What would you recommend? Parameters:

• Open-minded to ricey sounds. Or maybe lower rumbly sounds? You tell me
• Summit Racing because I have a killer coupon
• 2.5" stainless and polishable or already polished
• 3.0L inline six 2JZ
• N/A, eventually ITBs, evennnnntually turbocharged
• Zero packaging constraints. So much room under the back end.
• Tolerable dB level for cruising, but it's a hot rod, so don't mind a little loudness
• MUST LOOK COOL*   *cool being undefined

My vote would be a center inlet center outlet magnaflow. 

Dusterbd13-michael (Forum Supporter) said:

My vote would be a center inlet center outlet magnaflow. 

I'd definitely say that's not a bad choice, those generally sound pretty decent on most engines.  The really large case ones can get a little bit too deep, boomy and droney, but not the good kind of deep like the quieter Flowmasters.  So if more quiet is desired, I prefer to stay with the smaller 4x9 or 5x8 cases and just add more in series instead of going up to the big 5x11 mufflers. 

For my TR6, I went with a Borla XS.  Reasonable price for a stainless muffler and comes in lots of configurations.  The sound is good for my 2.5l straight six, a little more raspy than stock.  It sounds more like an Italian car now than British.

I personally can't stand "blatty" I6s like you get with mostly un-baffled stuff.  When it comes it I6, I like to keep the frequencies lower rather than higher.  High frequencies make most I6s (and many V6s) sound really obvious, and not in the cool way.  Just my personal opinion.

I would look to Magnaflow.  They do a 3" that sounds great

So THIS:

And not this:

Because the second one sounds like this:

If looking cool is a key requirement, it's hard to beat a Supertrapp - although they're only so-so when it comes to flow rate.

This is what a Borla XS sounds like on a TR6.

I never noticed how much slobber comes out of the tailpipe before now.

For an old hot rod I've always felt sidepipes are kinda peak cool factor, but with a straight 6 that might be weird.

I had Hooker AeroChambers on my truck for the longest time and I loved them.

I don't know how relevant that is though as my truck's displacement is your engine plus 2/3 of your engine.

The 'Camaro' style Magnaflow (12265 and 12267) transversely mounts the muffler and splits the single inlet to dual outlets. Might make for an interesting look.

ultimately it comes down to the sound and volume you want.

I found the best sound on nearly anything is when there is actual tailpipe after the muffler, gives the most character.

It if was me Id probably run a very small packed bullet, and then make 1 or 2 helmholtz resonators to control the interior sound.

I actually prefer higher pitched tones in most 6cyl cars, my 3mz Highlander has that exact exhaust solution, I just love it.  Nearly doesnt sound like a transverse v6 and has lovely outside tones with no intrusion on the inside.

With the inline 6 and a single pipe, it will sound fine no matter what imho.

I would go with a big fart can fast and the furious style.  Rainbow 3 or 4inch tip etc.  I think it will add a nice dichotomy to the build.

Yes, I'm serious.

Porter mufflers are practically required for a hot rod. Probably have to custom order the size you want but they can make it in stainless.

https://portermufflers.com/

For a really old-school sound, don't merge the two manifolds into one pipe/one muffler; keep it true duals. Back in the day guys would hack up stock I6 log manifolds with pipe fittings and a divider to get a split/dual outlet manifold.

MadScientistMatt said:

If looking cool is a key requirement, it's hard to beat a Supertrapp - although they're only so-so when it comes to flow rate.

Cocktail shaker tips on a Supertraps look tits. 

Another vote for Magnaflow. I love everything about them except the cost. In that vein, when shopping on Summit, AP Exhaust and Jones mufflers are indistinguishable from the Magnaflow offerings at a much better pricepoint.

I would suggest using the Avalon resonator under the cab, and then stepping the pipe diameter up to 3" thru the muffler and tailpipe. This is an attempt to future-proof the back half of your exhaust system as you will want full 3" plumbing after the turbo; you know, eventually. You can simply ditch the resonator at that time because the turbo will have such a massive effect on the exhaust note, you won't need the resonator anymore.

I've got a 2.5" Magnaflow on my Bavarian 2JZ. It is not a highway car and I prefer driving it with the windows and sunroof open so I like a little more noise. It's deep and mellow enough to not be annoying but get's rowdy when Vanos changes over.

This is super helpful, thanks guys. Forgot to mention I'm trying to fit the stock cat somewhere too, but not sure how that affects the sound. I'm open to experimenting. I need the TIG practice anyway.

The cat will likely give a few less pops and bangs unless you try to tune them in.  And it'll make it a little quieter.  But it shouldn't produce a big change in sound. 

In reply to maschinenbau :

the cat will just flatten the sound a little and reduce the intensity.  Basically meaning you can run less muffler

My car has a highflow cat and Magnablow on a stock tune. I've learned how to make it pop and bag a little on decel but it takes practice.

Another vote for Magnaflow, the straight through race cans in particular. They consistently sound the best to my ear regardless of platform or engine configuration. 

My RX7 has dual 3" pipes off the headers into a single 3.5" through a Magnaflow race can out  the back. Sounds great, a little different than the classic V8 rumble with a nice rasp to it, loud but not completely obnoxious.

My truck has dual 2.5" pipes off the stock manifolds, cats, x pipe, into dual Magnaflow chambered mufflers dumped at the rear axle. It's a bit "boomy" TBH and drones quite a bit. Going to run tail pipes out the back and probably add some resonators at some point. 

I am personally not the biggest fan of Magnaflow mufflers.  The rockwool has a specific (i call it crispy) sound that I dont care for, plus it breaks down after about 3-4 years, and usually by 5 years the packing is gone or nearly gone and ineffective.  Plus last time I checked...they are more expensive for their plain 409 stainless muffler vs a 304 Borla muffler, if you want polished its obviously more, they use a 430 stainless on the polished ones, but it still contains iron, so they still rust eventually.

Dont get me wrong...they aint bad, but they aint great.  Ive installed probably a thousand Magnaflows at this point and just see the same results over time.

I use to love their chambered mufflers, but the last handful I have dealt with the inner baffles were not welded (like the machine was just a bit off and missed them) causing them to rattle after a few cycles, I would have to drill holes and spot weld them from the outside.

For budget, use the Magnaflow straight thru knock-offs, Cherry Bomb Salute, Flowmaster Flow FX, Jones MaxFlow, etc etc they are all pumped out of the same factory in China and for $35-40 a muffler they are a bargain, and cheap enough to either repack when needed, or just throw away and buy another in a handful of years.  409ss case and core, the welds are usually regular steel. They use regular fiberglass for the bulk fill so I find they sound nicer then the rockwool in Magnaflows and dont have that crispy sound.

Another vote for a Supertrapp.    Just because.

I have a Sevens type car (Stalker) with a 3.4 V6. There is somewhat limited space for exhaust systems. I started with a Moroso auger style racing muffler at the end of the header with a down turn at about 45 degrees to the road. It was pretty loud. I added a Super Trapp with a band clamp to the end of the muffler. I've tried different amounts of discs and right now have 12 discs. It doesn't seem to hurt performance but has cut the loudness back to an acceptable limit especially for my wife.

Everyone is wrong, get a resonator and some tubing on Summit if you want but this is the Rice Rod.  Multiple Yoshimura cans is the answer, probably two or three of them depending on the displacement of the bikes they're intended for.  Pick your style: