As the title states... I want one bad! I don't mind losing low end as long as it makes up for it top end Anyone know? Or do I have to go custom?

 

www.enthuzacar.com
They make a 3 inch exhaust for the miata.

 

spike thanks for the link...however I noticed they just have catbacks... I just need a downpipe thats 3 inches... I was planning on getting custom piping after the downpipe to my muffler. ( obx muffler) Seems like that would be much cheaper IMO

 

No Miata vendors make a 3" downpipe. At least not off-the-shelf.

 

Are you using the GReddy manifold? The largest so far for that is supposed to be the BEGI downpipe. It's real tight back there against the firewall. If you have a custom manifold then you may have to go to a fab shop to do it. I had a 3"DP on my old setup (custom manifold too) as do other people, it's definitely possible to fit one in there.

 

I'd wait to see what BEGi comes up with. Even with a 2.5" to 2.75" the divorsed wastegate setup should prove to be better than a sraight 2.5" to the cat. Maybe you can work with Corky to make the bottom half step up to 3".

 

WOT mentioned a Miata he worked on at Flipside had a 3", I'm pretty sure it was a greddy system too, but it was a one-off job.

I'm just waiting for Begi's DP to come out, I'll run a 2.75-3" adapter to run a 3" cat and muffler. That's the plan anyway.

 

yeah... a lot of shops will tell you it wont fit.. and if you are using the stock manifold, it it will be hard... i settled for 2.5 dp and 3 the rest back...

 

just gotta do a little cuttin.

 

 

I have no real numbers on this but Jay Kavanaugh (miata.net / R&D @ Garrett) says a downpipe matching the exducer then with a divergent angle (I think 11 or was it 17°?) exiting the turbo is the ideal situaion. if you can somehow fit that in your engine bay, i think you'll get most of the benefit of the large exhaust....

 

Like this?

http://russmarshall.com/v/cars/cmc7/...10856.JPG.html

I had to modify the engine bay slightly ...
The cone is from Burns Stainless and it extends into the housing to block the wastegate.

If one could find combined cone and bend this could be done in a Miata.

hrk

 

Hahahahahaha!

I just noticed that on the main page of the forum the title of this post is truncated to "So I want a 3 Inch..."

With all the spam posts lately, only one thing immediately popped into my juvenile mind...

Sorry, for the thread-hijack.

 

exactly!

reality unfortunately dictates you can either bend first and then flare OR use a stubby flare and then bend. I'm torn but I think I'll be turning first and then flaring.

 

slightly... right..

 

Contact Rob at www.Flipsidecustoms.com. He fit one on his old Greddy setup. You won't lose any low end. Just nice spool and power gains.

 

YOU DON'T NEED TO HAVE A FULLY SIK 3" DUMP PIPE. You have your hand on your sausage. 3" is overkill on a 2L engine, what do you have?

Much more important is the velocity of the exhaust gases. The faster the gas, the better the exhaust system and bigger DOES NOT = faster flow. You will have LESS power with a 3" all the way through than with a matched custom system of about 2.5"(depending on your power level and capacity of course)

Do some reading, then get a 2.5" dump pipe.

60AGS

 

Full 3 Inch!

 

T25...do some reading on turbochargers...you're all wrong. Well, not all wrong, but mostly wrong.

 

+1!
again.

pressure ratio > *