EVO VIII twin scroll turbo...let's discuss!
 

greetings all,

i just completed my 1.6l diy turbo build. all is well, the car is a blast to drive. Thanks to the many board members who helped answer my various questions. I still consider myself a "green" mechanic, so I appreciate the helpful tips from everyone.

At any rate, I am going to start gather new parts to turbo a BP. I am considering turbo options, and I'm quite interested in the evo 8 unit. I like the fact that its a twin scroll unit, and I have a friend who does the most most amazing fabrication work ( works for ams), so a manifold is no problem.

my questions are:

1) how good of a match is the evo unit for the 1.8L.?. I am still having a hard time reading compressor maps, so an expert may be in order to answer this. I'd like to hear opinions on what spool might be like, also.

2) since im a college kid, I am doing the build on the cheap. should I have any problems running something like 8psi on the evo unit (using fuel bandaids) or should I go for a more conventional small turbo approach ( thinking 14b)

thanks,

-dan

how about a link?

I dont know what ams is.

AMS is a serious shop out of Chicago. They are mostly a Evo shop but also have one of the worlds fastest ka-t 240sx's. They make great stuff.

I'm surprised you haven't heard of them, they have some of the fastest time attack cars in the US.

http://www.amsperformance.com/main.php

never heard of ams!! for god's sake man, youre from chicago too!

http://www.amsperformance.com/ ....watch the vids and you'll freak.

in other breaking news, the germans surrendered, and europe is going to have to be rebuilt. jk

damn looks like someone beat me to it

Not to beat on poor Loki, but +1!!!

Back to the question at hand, the evo 8 turbo is pretty good. It might be a little big for a 1.6 but the 1.8 should be able to spool it ok. They're built to flow 20+ psi so you really wouldn't be fully utilizing it at that low of boost.

Alright thats a good line. I didn't know where the fuck you were from. Theres AMS's all over the fucking place.

And awesome that chicago is starting to get some cool turbo guys.

and DB the link was for compressor maps. or turbo specs

The evo turbo isn't overly different from the normal 16g's.

There's a lot of upgrades out there for them too. TME/20g/etc.. Of course, by the time you get into that kinda stuff, you could have gone for a GTK turbo or something else, price wise.

Heh, I was over at AMS for their new shop grand opening bbq. The new shop space is so damn nice.

The 16g is a pretty nice oem turbo, with a properly designed split manifold to take full advantage of the twinscroll it will definitly spool faster than a similar big 16g.

Dirty, update your location profile ;)

dont know much about the particular turbo but twin scrolls have been around for decades (factory on the early 90s turbo 4wd celicas). chances are you wont see/notice a difference over the same turbo with a single entry housing. perhaps if you designed the manifold like the factory did (however that is) you could realize the couple hundred RPM spool improvement but that would be it.

I Guess they keep the pulses from opposite ports away from each other to avoid the whole FM/BEGi "directed pulse" argument.

DB, clear your PMs, i've been trying to reply to yor PM all day, lol

as far as your build, sorry im no help, i still dont understand turbo maps either, but i assume you are considering the evo VIII turbo because you can getone for cheap/free from your frineds shop, if so go for it

i read a post by quirt crawford, of crawford performance, regarding the spool characteristics of equal length and non equal length manifolds. On the non twin scroll manifold, the powerband came on 750 rpm later than the twin scroll mani.

granted, this test was on a Subaru Legacy , but Im sure the same theory would hold true on a miata.

also, does anybody know if the all trac turbo is a version of the ct 26?
-dan

Of course on a subaru, with the exhaust ports on the bottom, there's a lot of ways to improve spool

care to elaborate

Well, consider this.. on the miata, with a log manifold, you've got about a foot of pipe from the exhaust port to the turbo. On a subaru, from #1 to the turbo (in stock location), it's like 6 feet, maybe more...

The exhaust ports are down by the lower control arms, the turbo is up by the passenger side firewall.

sorry OP but we're threadjacking a little biti used to own a bugeye wag fwiw

i understand what your saying, but i think your comparing apples to oranges. The size of equal length vs. unequal length headers in subaru's are almost the same. Plus, tons of dudes make 500 plus hp on stock headers ( im talking about usdm ej25s)...the real benefit of the eq length headers is the spool.

like i said, im a green mechanic so there is probably a flaw in my arguemnt. experts chime ..now

-dan
ps your avatar is hilarious

i know i know! the early alltracs used the single entry CT26. the 91-93 used the twin entry ct26. the 94 and newer GT-Four (same car, not imported to US) used the CT20B with the ceramic turbine (unofficial designation I guess?).


I have a cracked ct26 turbine housing in my garage. nice paperweight.

The evo turbo is a good option but, unless you are gonna run alot of boost a normal 16g will fit the bill for you. I have been considering steping up to one myself. fWIW a 16g when done right can get you to 300 hp so IDK how much farther you wanna go from there.

im guessing the twin scroll 16g will out spool a standard evo3 16g.

Im wondering if any other small twin scroll turbos exist? I am looking to do a low boost application because its cheap (bandiad and wideband type build) and I dont know if i can: 1)afford megasquirt, or 2) if i can get a hang if the megasquirt thing---as i said im a greenhorn to this turbo thing

with that in mind, can anyone make an estimate of what power would be at with 8psi out of the evo8 turbo on a 1.8L

you guys do realize that the evo 3 is the only off the shelf 16g that will work for us guys running a normal 16g setup right? the evo VIII is a different inlet design
Evo VIII
http://www.turbo-kits.com/images/sto...bochargers.jpg

Evo III flange
http://i153.photobucket.com/albums/s...5/DSCF0008.jpg
FWIW i made 176 mustang dyno whp(200 dynojet ;) ) at 8-9 psi on my 1.6 with a small 16g. I make boost before 2K and make more than 100 lb/ft before 3K easy.

yeah understood for sure. i want to do the twin scroll thing if i can. if i cant find a suitable twin scroll turbo, then ill just do a 14b and sweet tubular mani

If you are low boost then a 14b or 16g will be more than enough for you to be happy. The main adavantage to the other turbo's on our smaller motors is the top end breathing. The evo series strives to have the same or similiar low end effeciency of a small 16G/14B with better high boost flow 17+ psi than the big 16g's.

another possibility - the IHI vf38 from the JDM Legacy... also twin-scroll, titanium turbine wheel, dual BB. OEM rated at 280ps, which is pretty much on the edge of the tranny danger zone. Still a somewhat oddball flangetho.

It used to be pretty cheap 'cos the WRX guys couldn't do much with it.

Fuck that, I would stick with something common. Put a standard mitsu flange on there, rock out with your cock out. I don't think you're going to pick up 700 rpm spool with the twin scroll.

yeah, been looking on nasioc for a vf37 but its way too pricey. havent looked into a 38 but its a possibility.

if any suby guys are lurking around this thread, i bet a single turbo off a legacy b4 would be great. I bet that spool would be incredible .

now you're just being a cottonheaded-ninnymuggins

seeing as im planning on one hell of custom mani (have all necessary flanges), why not do the evo8 turbo.

tons of people run standard 16g turbos, i dont understand why i wouldnt see a signifiant reduction in lag over the standard unit...after all, thats why mitsu designed a twin scoll turbo in the first place.

fwiw, im like 70% sure ill be going with the evo 8 snail. ill be sure to bump this thread when the boosting begins this summer


-dan

maybe it's the stock manifold, but the evo 8 with the standard turbo isn't exactly a fast spooling beast.. i know a little bit about mitsu turbos.. we just got 80 grand worth of delivered today..

Dude Nester has turned quite a few Before he left KY i was always hitting him up for parts etc. The normal 16g or a 14b will do the job easily and effeciently. Ask juhanis how he likes his 14b vs the 16g he has pmed me before that the spool etc and low boost performance was quite nice for him. In a low boost app, you don't need a 600+ cfm turbo for that.

can you make a few of those fall off the truck jk
if one falls off the truck, pm me. i have cash in hand.

i never said the 16g was the fastest spooling turbo (which i itself is reason enough for a twin scroll), i just stated that i figured a twin scroll 16g setup would noticeably better than an standard 16g setup.

http://www.bittermancircle.com/my%20...tDeadHorse.gif
phew

-dan

Awesome picture

what do you have against standard 16g setups, huh ? :magna:

(other than the later full boost and whatnot)

nothing much, im partial to smaller turbo setups...i was just going to do a 14b setup. But, due to my hookup on the manifold and turbo, i figured why not.