more restrictive muffler = quicker spool?
#24
Baffled/chambered mufflers are dogs, check this out.
http://autospeed.drive.com.au/cms/A_0382/article.html
I have decided on a 2 1/2" system with a hooker max flow. Its relatively cheep and known to flow the same as a straight pipe.
I am still trying to decide if I should go out the center and have to mod the bumper (any advice on this?), or just stick with the standard routing.
http://autospeed.drive.com.au/cms/A_0382/article.html
I have decided on a 2 1/2" system with a hooker max flow. Its relatively cheep and known to flow the same as a straight pipe.
I am still trying to decide if I should go out the center and have to mod the bumper (any advice on this?), or just stick with the standard routing.
#25
A little history on the "Turbo" muffler.... When Chevrolet started developement of the Corvair turbo they needed a high flow but quiet muffler. After 3 years of experimenting they came up with the 3 tube design we are all familiar with today.
In my opinion a quiet exhaust on a turbo car is better because you can really sneak up on folks that way.
In my opinion a quiet exhaust on a turbo car is better because you can really sneak up on folks that way.
#26
I have a Thermal 3" straight through muffler on my enthuza exhaust. Before that I had a 2.5" dynomax that sounded just beautiful. I liked the way the dynomax sounded over any other muffler that I have heard on a miata. The Thermal is fairly quiet but its VERY deep...you dont hear any turbine whistle in the exhaust at all. With the Dynomax I could hear all kinds of turbine spool and it just sounded downright dirty.
#28
Baffles for the lose. If you have a turbo, a bullet style glass pack is plenty quiet. I have a dynomax 3" bullet on mine. It sounds mean, just a lot of roar and whine. The only 4 bangers that come close in terms of deepness are the unrestricted subarus (essentially the same design). Resonated 4 bangers (read hondas) sound tinny and buzzy.
#29
on a turbo car the exhaust rather than being pulses is a swirl because of that using a flowmaster or Baffle type muffler is quite restrictive. The reason is the swirl hitting a baffle breaks up and makes more or less a wall inside the muffler that all the exhaust has to force it's way through. Conversley the turbo tripple tube muffler the swirl is directed around the muffler intact therefore no restriction is added from pressure walls. When I get my Miata and turbo it I will be using a turbo style muffler.
#30
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I ran it with a 3" glass pack and cat. It was so loud under load that I couldn't hard hear the person next to me. It's 3" from the turbo to the tail pipe, straight out the back. It's not race car loud, it's street car loud. I want to be able to hear the person next to you when you're on the throttle. The turbo muffler provides that.
#31
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i still stand by my system. i know i've whored it before.
turbo to 3" cat, 3" bullet muffler resonator (stock location), 3" GIANT magnaflow straight through muffler. no drone, no crazy loud, no nothin. i think it sounds phenomenal when you get on the gas, but it doesn't hurt your ears or conversations. compared to an N/A car with an RB header, roadstersport midpipe and roadstersport muffler section, it's way quieter and better sounding.
turbo to 3" cat, 3" bullet muffler resonator (stock location), 3" GIANT magnaflow straight through muffler. no drone, no crazy loud, no nothin. i think it sounds phenomenal when you get on the gas, but it doesn't hurt your ears or conversations. compared to an N/A car with an RB header, roadstersport midpipe and roadstersport muffler section, it's way quieter and better sounding.
#32
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Got the Miata back together today and did 3 consecutive boosted runs. Here's what the turbo spool looks like with the different mufflers. Nothing else was changed and ambient temps were nearly the same. I'm running a 3" exhaust from the internal gate to exit, with a 3" universal cat and no bends except for the drop down and back on the downpipe.
Cheap 3" turbo style muff offset/center exit:
Cheap 3" turbo style muff offset/center exit:
onset = 1480
3psi = 2780
6psi = 3350
9psi = 3790
12psi = 4170
Chambered "flowmaster style" muffler:3psi = 2780
6psi = 3350
9psi = 3790
12psi = 4170
onset = 1820
3psi = 2910
6psi = 3550
9psi = 3920
12psi = 4410
3psi = 2910
6psi = 3550
9psi = 3920
12psi = 4410
#37
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I guess I was suckered in to all the hype surrounding these mufflers, but apparently they flow like crap- at least on a turbo'd 4 banger. And believe me the turbo muffler I installed is no example of good flow design.
hrk- is this for the locost?
hrk- is this for the locost?
#38
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Every Jim Bob and Cletus around here have a pair of em under their truck with a whole mess of shitty crush bent aluminized steel piping leading up to them. All the hack *** muffler shops push them cause they have a better margin then Magnaflow or something decent. There are a few things I don't like just because of the people I see use them. Call me a piece of **** or whatever but thats the way it is. I hate Flowmaster, Penzoil, Nascar and wearing overalls with no underwear and a flannel "vest"
#39
Got the Miata back together today and did 3 consecutive boosted runs. Here's what the turbo spool looks like with the different mufflers. Nothing else was changed and ambient temps were nearly the same. I'm running a 3" exhaust from the internal gate to exit, with a 3" universal cat and no bends except for the drop down and back on the downpipe.
Cheap 3" turbo style muff offset/center exit:
Cheap 3" turbo style muff offset/center exit:
onset = 1480
3psi = 2780
6psi = 3350
9psi = 3790
12psi = 4170
Chambered "flowmaster style" muffler:3psi = 2780
6psi = 3350
9psi = 3790
12psi = 4170
onset = 1820
3psi = 2910
6psi = 3550
9psi = 3920
12psi = 4410
3psi = 2910
6psi = 3550
9psi = 3920
12psi = 4410
#40
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I could produce them. The muff is the last flanged section of my exhaust. I already have a straight pipe section to bolt in, so it's just a matter of 3-bolts off, 3-bolts on. And I've got some reusable copper gaskets coming. I'd planned on doing it on the dyno- when that day comes. Still have some street tuning to complete and an EBC to get working before I go. Should be sometime this month. I'll post back when I have results. Would be nice to swap out the cat too, but welded it in to the center section of my exhaust that runs from the dp to the tail section. - rob
Last edited by m2cupcar; 01-03-2007 at 12:05 AM.