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2.25 or 2.5 exhaust?

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Old 07-29-2008, 04:45 PM
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Default 2.25 or 2.5 exhaust?

Hey so im relatively new to this forum and ive got a pretty simple question.

in the future im looking to turbocharge my car. im looking to do some modifications to my car while im saving money for the turbo. and in order to not be counterproductive i want to see if i get a 2.25 in exhaust from flying miata will it still work with a very small, entry level turbokit such as the BEGI-S with the T2554 . so will the 2.25 in" midpipe and exhaust from flying miata that is meant for N/A miatas work alright with that turbo or will i need the 2.5 in like it says on the FM site? what would happen if i got a 2.5 in and didnt end up getting the turbo? would i lose power? i know backpressure is a concern in there somewhere but im not gonna pretend i know what im talking about with that..

thanks in advance - Esp140
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Old 07-29-2008, 04:52 PM
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The 2.5" without turbo will be loud. I haven't heard one but I'd imagine it's LOUD. The 2.25 pipe with turbo will hurt spool and power. Why not just wait?
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Old 07-29-2008, 05:02 PM
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3" or bust.
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Old 07-29-2008, 05:10 PM
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I had a 2.5" system on my 90, including a cat and a 'turbo' muffler. With the turbo it was quieter than my friend's Evo9. Once I took the turbo off, it was annoyingly loud.
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Old 07-29-2008, 05:12 PM
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Originally Posted by Braineack
3" or bust.

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Old 07-29-2008, 05:19 PM
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4" or 5"
jp
seriously though, id wait. If you dont know if you will run a turbo or not, why make a decision that will depend on whether your turbo?
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Old 07-29-2008, 06:21 PM
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Wait on the exhaust.

Everyone posts 3" but with low boost stick with 2.5" with a straight throug mid-pipe.


Take a look at these http://www.enthuzacar.com/

And read this page, it will help you pick an exhaust.

http://www.enthuzacar.com/faq.asp
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Old 07-29-2008, 06:33 PM
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3" or wait for your ***** to drop and then do 3"
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Old 07-29-2008, 08:04 PM
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Originally Posted by esp140
Hey so im relatively new to this forum and ive got a pretty simple question.
After shipping, you're going to be into that FM exhaust for close to $500. I've seen standalone Megasquirts and even an MSpnp for that same amount.

You absolutely do not want to go 2.5" now. The biggest you will be able to live with on the street NA is 2.25". And there's nothing wrong with throwing a turbo on that small of an exhaust, but it's going to hurt performance. I'd say it's probably worth about 15-20% in every boost category over a 3" exhaust... more power=more loss. Take a 200whp 2.25" Miata and put a 3" on... with no other changes, gain 20whp and 300rpm spool.

There is no decision here. If you have dreams of turbo, wait until a 3" is in the cards.

And for the money, Enthuza is the only way to go. Just wait until you've made up your mind. And I'll also add that if you're going to stay NA, wait until the things you want pop up in the classifieds.

Being a NOOB, you'll also want to put your location in your profile and whatever you currently drive in your signature.
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Old 07-29-2008, 08:11 PM
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Originally Posted by gwilo
Wait on the exhaust.

Everyone posts 3" but with low boost stick with 2.5" with a straight throug mid-pipe.

Yeah, because we're all a bunch of ******' jokers. Who needs better spool and more power anyway?

3" or GTFO. Don't do an exhaust on your car before you are turbo.
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Old 07-29-2008, 11:21 PM
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cool, thanks a ton for all the speedy input.

i can clearly see the consensus is to wait until i got the dough for the turbo..which will be next summer when my job starts up again after school. ill for sure look into enthuzas and ive read about megasquirts but they seem way over my head but i got plenty of time to keep lookin into them.

ill have a part time job during school so i can do small modifications until i pick up my other job...do u guys have any suggestions on what i can do/buy in preparation for teh BEGI-S?

thanks again for all the input im pissed i've waited so long to post lol
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Old 07-29-2008, 11:30 PM
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Originally Posted by Savington
Yeah, because we're all a bunch of ******' jokers. Who needs better spool and more power anyway?

3" or GTFO. Don't do an exhaust on your car before you are turbo.
I agree 3" is the way to go,

but he said small turbo 'BEGi S' for that size a 3" exhaust is a waste of money and there will be no gains over a 2.5". He will loose low end power and will not have enough PSI to enjoy the high end gains.
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Old 07-29-2008, 11:31 PM
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megasquirt /thread
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Old 07-29-2008, 11:51 PM
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Originally Posted by johndoe
megasquirt /thread
so ur sayin get the megasquirt now..build and tune for my N/A miata then when the turbo comes retune and use as a standalone EMS?

sorry if im not usin terms or n e thing right im barely comprehending

Edit: thers not PNP-MS equivalent for the NB's is there?
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Old 07-30-2008, 12:23 AM
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Ok nooby, keep reading quit posting...

You just now declared that you have an 01, which proves exactly why we assrape all you noobies that don't have a proper sig...Had everyone known that you have an 01, people wouldn't start throving the MS at you. The MS is the best thing you can do to your car if you do not have to pass emission, but since you have an 01, that's another story.

I recommend to you, set aside your little ego, leave the car bone stock and start saving every penny and do it right the first time...so what if all your friends are calling you gay at the moment, it will be payback time once you are properly turboed.

If you must **** with something, start witht he suspension, but that will set your turbo goal further back if you are tight on the monies...
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Old 07-30-2008, 12:44 AM
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Originally Posted by gwilo
I agree 3" is the way to go,

but he said small turbo 'BEGi S' for that size a 3" exhaust is a waste of money and there will be no gains over a 2.5". He will loose low end power and will not have enough PSI to enjoy the high end gains.
Do explain how a 3" exhaust will lose power *anywhere* over a 2.5" exhaust on a turbo car.
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Old 07-30-2008, 01:07 AM
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I can't comment on the turbo part but in my non turbo miata, I drive a 2.5 with no cat but a resonator instead and a borla. To me it's not TO loud but loud enough where I like the sound. Cops dont even second look at me oh wait your not getting a borla so IDK. But with mine im happy. Dont know if this helps or not seeing as the only thing relevant is mine is 2.5 inches.
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Old 07-30-2008, 01:09 AM
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go 2.5
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Old 07-30-2008, 01:11 AM
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Are 3" exhaust inherently louder than 2.5"? Not sure of noise and size relationship or if there even is one. How about drone/buzziness?
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Old 07-30-2008, 07:59 AM
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Originally Posted by Savington
Do explain how a 3" exhaust will lose power *anywhere* over a 2.5" exhaust on a turbo car.
I was wondering the same thing?

Originally Posted by kenzo42
Are 3" exhaust inherently louder than 2.5"? Not sure of noise and size relationship or if there even is one. How about drone/buzziness?
Generally, with all else being equal, yes they are louder.
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