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Time to figure out a new exhaust... Suggestions?

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Time to figure out a new exhaust... Suggestions?

Old 02-29-2016, 06:23 PM
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Default Time to figure out a new exhaust... Suggestions?

Well, I currently have the Flyin Miata Duals and before the turbo I LOVED their sound. I would like to replicate that type of sound with the turbo.

I am having a new 2.5" exhaust made from the turbo to the tips This will likely start next week. So I have to hurry the heck up and figure out what I am going to put under there.

There will be no cat. And nothing of the stock system reused. I do however, want to stay with a dual exhaust look, as the bumper is already cut for it... and I just like how it looks.

Any thoughts or suggestions? I know Exhaust sound is subjective.. But I don't want it to be loud, but would love a growl and burble like the FM exhaust had.
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Old 02-29-2016, 06:29 PM
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Honestly why 2.5" instead of 3"? Cost difference when diying is marginal, it will help spool, and with a good muffler would not be much louder then 2.5".
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Old 02-29-2016, 06:34 PM
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Because from everything I have read the last few weeks, it would suggest that at my targeted power levels a 3 inch exhaust is not only a waste, but a hindrance.
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Old 02-29-2016, 06:38 PM
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You suck at reading something terrible then. Try again.
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Old 02-29-2016, 06:41 PM
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It wouldn't be the first time.
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Old 02-29-2016, 06:43 PM
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3" is better. Ignore power goals, you gain a significant amount of spool.
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Old 02-29-2016, 06:43 PM
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bottom line - unless you have a really good/compelling reason not to go 3" (like, you already have a 2.5 or can get one for super duper cheap), you always want 3"
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Old 02-29-2016, 06:45 PM
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alright, then, 3" it is.
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Old 02-29-2016, 06:46 PM
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Originally Posted by viriiguy View Post
Because from everything I have read the last few weeks, it would suggest that at my targeted power levels a 3 inch exhaust is not only a waste, but a hindrance.
you werent reading on this site then...

you want a 3" exhaust with the largest straight through muffler you can fit.
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Old 02-29-2016, 06:47 PM
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Originally Posted by Braineack View Post
you werent reading on this site then...

you want a 3" exhaust with the largest straight through muffler you can fit.
Admittedly, most of my exhaust ideas, came from a few M.net threads and various google results.

*Bad Randy* Bad Bad!!
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Old 02-29-2016, 06:49 PM
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reading m.net is a 100% guarantee for failure and aidz
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Old 02-29-2016, 07:46 PM
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Ok, so 3 inch to the axle. Then maybe a magnaflow or vibrant with dual exits
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Old 02-29-2016, 08:49 PM
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3" all day.

As far as sound, magnaflow/or knockoff (xlerator) will get you a similar sound as the flying miata kit as well as piece of mind that you are getting the least amount of restriction possible.

However, i enjoy the sound of the 40 series flowmaster better. it has more tonal quality over the magnaflow. i would recommend using a resonator with it as it tends to drone.

in your particular case if you were interested in running a flowmaster and still keep your duals the 80 series is a transverse muffler will work.

the flowmaster is a baffled muffler and does restrict the exhaust a bit but not much, i do notice a difference when running between the two.
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Old 02-29-2016, 09:53 PM
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there's no point in doing 3" if youre going to run a redneck muffler.
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Old 02-29-2016, 10:02 PM
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There is if you want to "feel the thunder" in your loins...
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Old 03-01-2016, 05:27 AM
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Originally Posted by Braineack View Post
there's no point in doing 3" if youre going to run a redneck muffler.
And what muffler would you suggest?
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Old 03-01-2016, 05:47 AM
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Magnaflow 5x11x22 is miataturbo recommended muff



I run the center/offset one, it's a single chamber straight thru. The center/center is a dual chamber, supposed to be quieter.

You could do duals still, maybe. This is ARtech stuff, not manly 3" though.

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Old 03-01-2016, 06:31 AM
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It looks like the Magnaflow 12198 will work. And I will add a resonator to take away some of the highway drone.
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Old 03-01-2016, 08:32 AM
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I love my Artech stuff

3"
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Old 03-01-2016, 08:36 AM
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My favorite is:

leave the turbo at the same ID as the turbine outlet

either cone shape, a 5 to 7 degree, or use a series of shallow swages to reach a dia of 3.0

put the 3.0 end about 10 inches aft of the engine/tranny joint

create a 1 into 2 joint (Y) with the two legs of 2.25 each. two 2.25's are bigger than 3.

two parallel 2.25 tubes back to the diff, then turn one left and one right. This is the only time in modern society one can turn left in an acceptable manner.

add a foot long 2.5 id glass pack to each leg and then out the back. If a drilled core is not available use a punched core and run it backwards.

Add a nice pair of ****.
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