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Twin Scroll on a Miata, anyone else do it?

Hey,

I am going to be putting a twin scroll evo xiii turbo on my miata in the coming months, im wondering if there is anyone else who has done this and can offer some advice. I spoke to someone from Full Race at a recent meet who told me that the EVO VIII turbo would not work properly on a miata because the exhaust is on the driver's side. He recommended i pick up an EVO X. My buddy who sold me the turbo knows a thing or two about them (he has a 900whp silvia, and has had several miatas). He told me that since the turbo will be mounted in such a way that it is essentially parallel with the top of the motor that that shouldnt matter. I dont know much about this stuff, so im wondering if anyone else has put a VIII turbo on their miata successfully because im lazy and dont want to go through the hassle of selling this and picking up an X if the VIII will work.

I own one that I one day wanted to put on my TC. The main issue has nothing to do with the fact that its a dual scroll. The problem is that the downpipe flange is not perpendicular to the turbine inlet. Because it is angled at like 45deg or so it greatly limits the range that you can install it in. Also, I hope you got the smaller turbine housing. Most of them are rather large.

yeah, the issue was never twin scroll. The X is twin scroll too. My question was more, why did the fact that the exhaust is on the drivers side in the miata make the guy from Full Race tell me to use an EVO X turbo instead of the VIII? Is it due to the downpipe flange being at that angle as you described? or is it because the turbine is designed to spin in the opposite direction or something like that?

Here's some advice, STFU and I won't beat your ass.

wow, what a ridiculously redneckish thing to say... *crickets*

oh hustler baby, come over here and beat MY ass with your sexy vbands >:3

Then we can take turns on who is the pitcher, eh?

There was a huge post over on MR2OC a few months ago about the benefits of twin scroll on a 4 cylinder. The general consensus was that there is very little to be gained because the exhaust pulses are just to far apart.

This Jike kid is amusing....

update: I just spoke to someone else who knows what i have, and knows what they're talking about. The reason why the kid from Full Race said that is because he was probably thinking that I was using a regular evo viii twin turbo manifold. I just went to the shop where MY manifold is being custom built and the guy I have building the manifold told me that the reason why it would "not work" is not true, it would work, but the full race dude was probably thinking that i was using a stock evo manifold which would require a shit-ton of modification to get it to go, and even then it would not work efficiently. My welder/tuner friend then went on to inform me that the guy from full race WAS RIGHT about the evo x turbo being a better idea, but only because it would be an easier job to do because it wouldnt 100% require me to have a completely custom manifold.

*sigh* idk, im just selling this thing

Quote:

Originally Posted by zoomin (Post 449304)

This Jike kid is amusing....

Are you not entertained?

http://weblogs.baltimoresun.com/spor...gladiator5.jpg

Seriously though, besides having the turbo, why do you want to use a twin scroll on the miata? If you want to be really different, go with a rear mount turbo. That would be cool as hell.

the twin scroll spools fast and has very little turbo lag. AND, I already have one lol.

buy my turbo, manifold, and downpipe for sale in the "for sale" section and you'll never have to worry about spool.

Quote:

Originally Posted by dustinb (Post 449368)

Seriously though, ...go with a rear mount turbo. That would be cool as hell.

Im looking into it as we speak...

Quote:

Originally Posted by dustinb (Post 449368)

If you want to be really different, go with a rear mount turbo. That would be cool as hell.

:facepalm:

Quote:

Originally Posted by jike spingleton (Post 449352)

update: I just spoke to someone else who knows what i have, and knows what they're talking about. The reason why the kid from full race said that is because he was probably thinking that i was using a regular evo viii twin turbo manifold. I just went to the shop where my manifold is being custom built and the guy i have building the manifold told me that the reason why it would "not work" is not true, it would work, but the full race dude was probably thinking that i was using a stock evo manifold which would require a shit-ton of modification to get it to go, and even then it would not work efficiently. My welder/tuner friend then went on to inform me that the guy from full race was right about the evo x turbo being a better idea, but only because it would be an easier job to do because it wouldnt 100% require me to have a completely custom manifold.

*sigh* idk, im just selling this thing

what?

im kinda pissed i didnt look into twin scrolls, when i bought my turbo(3071r), they just wernt as popular with the tunner scene 2 years ago, now twin scroll housings are everywhere. i woulda had my manifold built for twin scroll and had a sick setup

if its from a fanboy racer, you know its fast.

Quote:

Originally Posted by mike_671 (Post 449519)

:facepalm:

lol, I joke I joke :P

Quote:

Originally Posted by hustler (Post 449558)

if its from a fanboy racer, you know its fast.

Word!

Quote:

Originally Posted by ctdrftna (Post 449530)

Look into quad scrolls and be ahead of everyone now.

Twin scrolls do it sooner. Spool that is. And you should look into the new hot thing -quick spool valves for twin scrolls- if you've got money and really hate to wait for spool.

http://www.spracingonline.com/images/products/3659.jpg
http://www.spracingonline.com/images/products/36594.jpg

Quote:

Originally Posted by sixshooter (Post 449645)

Hmm that actually makes a lot of fun sense. Closing off one "scroll" effectively makes the turbine much smaller, greatly helping spool. You'd need a non-twin-scroll manifold however, but that's easy & more common anyway.

What's the smallest twin scroll turbo?

Quote:

Originally Posted by Midtenn (Post 449303)

Subaru, Mitsubishi, and Porsche must not read MR2OC.

why do people think a small single turbo would have much lag. If you're worried about spool and lag just run a gt2554. Its not like its a vette and you cruise at like 1500-2000rpms. most likely you will already be in your "good spool" range while just driving around

Quote:

Originally Posted by Sam Amporful (Post 449734)

+ 1 .....60mph in 5th gear is more or less 3k rpm in most miatas

I farted while driving once and my gt2554r spooled. It's true.

Quote:

Originally Posted by TurboTim (Post 449647)

T3 housings come in twin scroll and they make those valves in T3, T4, and T6 if I read right. And that's not the only company now making them.

Quote:

Originally Posted by Jike Spingleton (Post 449724)

Subaru, Mitsubishi, and Porsche must not read MR2OC.

There are other factors involved, but there was some testing done with the GT30 single scroll (SS) (.63 A/R) and GT30 twin scroll (TS) (.78 A/R) on MR2s and there was neglagiable spool gains (if any) from the TS. With the MR2 already being a TS turbo from the factory, many people assumed a twin scroll would react better. The TS did make better high end power, but that was general accepted as being due to the larger A/R. Most of the post discussed how to properly utilize a TS turbo in terms of the wastegate(s).

I am not saying there isn't gains to TS turbos, but there is a lot more to it than just slapping one on and expecting a monster spool gain.

I found the post w/ dyno plots:

Quote:

Originally Posted by ATS Scott

Bruce, I now have an answer for you. But first a quick summary of set-up…
Oh and for those folks that have not read the whole thread:
SS=Single scroll
TS=Twin scroll

Both set-ups are re-routed, with 3" DP's. The SS was a .63 A/R exhaust housing, and a SS ATS adapter, and the TS was the .78 A/R with Divided adapter. Everything else remained the same. I used my EVC5 Boost controller, and used the peak hold feature for consistancy. I was shooting for 17 psi on all runs, as that is what I run on the street with 93 octane. All runs were done on 93 octane. One thing I noticed immediately, was the SS required lower settings on the BC to make 17.3 psi, where the TS needed higher settings to make 17.2 psi. That was the first clue. I got it tuned for just under 12.0:1 A/F and managed a 395 rwhp run. Dangerously Lean made more power (413 rwhp)

Next up was swapping back to my TS set-up and attempting to duplicate the results. This is as close as I could get. TS is run 58, SS is run 19:

http://www.atsracing.net//dyno%20run...01.2%20bar.jpg

I wanted to see if dangerously lean would pick up the power of the TS, it did, but nothing like the SS. TS is run 54, SS is run 16.

http://www.atsracing.net//dyno%20run...bar%20LEAN.jpg

From my datalogs, the SS consistantly hit 1.0bar boost at 3900 RPM, and the TS at 4000 RPM, even though the TS was beating the SS to 200 ft/lb by 100 RPM. (3400 vs 3500 RPM) at the 3400 RPM mark the SS was consistently ahead at .6 bar vs the TS at .5 bar. So the SS was building boost faster than the TS, but the TS was still spooling slightly faster. After 4400 RPM the TS just falls behind.

So Bruce, I say TS advantages are a myth on a GT30 turbo. This makes me want to ditch my TS set-up...

Unless I'm reading it wrong, the twin scroll maybe spooled a tiny, tiny bit faster down low, but made less up top?

Besides the fact, they have different A/R's, which kind of makes the comparison irrelivant

You should rather want a slight, and I mean "slight" because it probably is, worse spool rate than making your turbo choke in higher rpms. Cruising in a miata your rpms arent low, racing your rpms shouldnt be that low. Theres not worth while difference especially if you lose some up top, but I guess its not common and still cool or whatever.