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Old 07-25-2007, 06:51 AM   #1
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Default 2.5" to 3" and turndown q's

Well at this time I can't quite afford the enthuza 3" exhaust that I want, but I still want to make max power out of my system when I get it.

I was thinking about either getting a 2.5" to 3" adapter, going to a 3" resonator to a turndown tip (I saw something similar to this somewhere around here). My question is, is there any danger of melting my rear bumper supports? I previously ran just my midpipe (na and no turndown) and melted everything behind my bumper cover.

My other question, would a 3" resonator be that much better than a 2.5" for flow? Is the adapter needed? And I'm also not sure if I'm going to run a cat, would a 2.5" cat take away much power? And if a cat muffles the exhaust, then I might just try and run a cat with a turndown. Would that be overly obnoxious?

Sorry for the barrage of questions, but I really don't know how much the turbo muffles the sound, and how much piping diameter effects power and spool.

Answers and input will be appreciated.
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Old 07-25-2007, 07:05 AM   #2
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I think a Full 2.5" exhaust would be Ideal and "best" for the budget. You can go with 3 if you want, But if it were me, I wouldnt unless I had a huge turbo, etc. Just get a used cat for as cheap as you can, and hollow it out for a test pipe. or just have the muffler shop make you one (if they will since your in cali) Even with one of those Canister exhausts, it shouldnt be TOO loud. Because Thats what I have Name:  000_0021.jpg
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Old 07-25-2007, 07:07 AM   #3
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BTW, also, I would go to your muffler shop, and get a Custom exhaust made! Cheaper then a "brand name" exhaust, and just choose a muffler you want them to weld up on there for ya.
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Old 07-25-2007, 09:59 AM   #4
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Quote:
Originally Posted by Slidin'Miata916 View Post
BTW, also, I would go to your muffler shop, and get a Custom exhaust made! Cheaper then a "brand name" exhaust, and just choose a muffler you want them to weld up on there for ya.
Enthuza's stuff is damn nice for the money... I would never try to steer someone away from Jason's products. Personally, I made my own.
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Old 07-25-2007, 10:09 AM   #5
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Quote:
Originally Posted by speedf50 View Post
My question is, is there any danger of melting my rear bumper supports? I previously ran just my midpipe (na and no turndown) and melted everything behind my bumper cover.
not if you use the turndown.

Quote:
My other question, would a 3" resonator be that much better than a 2.5" for flow? Is the adapter needed?
the best flow is to step up from your DP, but not say a 2" to 3" exhaust. It's also important to either stay one size, but don't get smaller.


Quote:
And I'm also not sure if I'm going to run a cat, would a 2.5" cat take away much power? And if a cat muffles the exhaust, then I might just try and run a cat with a turndown. Would that be overly obnoxious?
It's not going to muffler the exhaust nearly enough. If you're thinking of a 3" exhaust, no reason not to do a 3" cat now.

With just a cat and no muffler, I suspect it will sound like this: http://www.youtube.com/watch?v=HxCO3EVoQtI
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Old 07-25-2007, 02:34 PM   #6
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[QUOTE=Personally, I made my ownQUOTE]

Lmfao.
Ditto.
:gay:
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Old 07-25-2007, 02:44 PM   #7
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A 3" exhaust will help flow on even the smallest of turbos. I'd love to hook up a 2.5" catback and log the difference in spool times vs. my 3" Enthuza.
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Old 07-25-2007, 02:45 PM   #8
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Heh, you are mentioning my under car exhaust... It's temporary... well... maybe.

BTW... I support full 3" for all DP and Exhaust stuff on turbo cars. Unless you can fit larger
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Old 07-25-2007, 03:26 PM   #9
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Turn down tips make it louder from inside the car.
BTDT!
I couldn't believe it at first, but it's true!
Point the exhaust to the back, like normal!
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Old 07-25-2007, 03:47 PM   #10
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im gonna replace my cat with one of these:

http://store.summitracing.com/partde...5&autoview=sku

stfu hippes.
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Old 07-25-2007, 03:53 PM   #11
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I uh...don't have one ATM
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Old 07-25-2007, 03:58 PM   #12
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Old 07-25-2007, 04:43 PM   #13
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Well I have a 2" test pipe that I got off of e-bat, and it was kinda cool, but after a day the smell really started to **** me off, so idk.

Would a cat like this http://store.summitracing.com/partde...5&autoview=sku
mess up my flow that much?

And I think I'm going to try and make my own for now, as I have a friend with a welder, and I just spent all of my $$ on my voodoo II. I'll look into muffler shops and see how much they want, but the reason that I was looking into turndowns and other simple options was to save $$.

Slidin, do you have a sound clip of your car?
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Old 07-25-2007, 04:57 PM   #14
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I've got a brand new 3" universal catco high flow.... if you do want to go that route.
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Old 07-25-2007, 05:12 PM   #15
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Magnaflow (Carsound) Cats are good high-flow cats.
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