From what I understand the extra stroked capacity (and CDB/forged internals) of my 2.1 makes the SC46 a more responsive package, but that on a 2.0 is less of match, from my understanding. There are some folks on here very happy with a 46 on a 2.0. On a 2.0 I'd personally go with a SC42.

I'd listen to the mapper - they see so many applications and combinations that their opinion is well worth listening to. That's why I went with my package - it was put together by Alan and Martyn and I follwed their lead. I resisted chasing big top end HP figures and opted for a torquey driveable car across the range. Also, dynographs tell half the story - on the road characterstics count for a lot and the mapper/tuner is in a great position to comapre by the seat of their pants.

I'm sure whatever you go for it will be an informed choice and you'll be happy. Good luck.

has anything else changed on the car other than the turbo?
Trev

LMAO - hardly any of that engine remains standard except the internals ;)
FMIC, oil cooler, billet fuel rails, bigger injectors, FPR, the list goes on. Steve has spent a lot of money on the old girl!

I can remember meeting him years ago when the car wasn't all that old and he hadn't started the journey to the 400 club!

Kenny was looking at an SC46 for his 2.0 STI Type UK, but apparently Kev @ Scoobyclinic advised against it, saying it's more suitable for larger capacity engines (I'd imagine 2.35 or 2.5 would be ideal).
He went with a '42 in the end and the results look very impressive, especially if you compare the results between his car on a turbo rated to 420 and Steve's on a turbo rated to 450!

I noted Andy Forrest has recommended the billet 321T on a 2.0 on here due to the better spool characteristics in comparison to the old one, and quite a few people who've posted on the 321 thread indicate that they barely notice a difference between their VF35 spool and this turbo which sounds nuts given the increase in power!
It seems the two turbos are quite well matched in terms of spool and top end :)
Comparing those graphs, the SC42 seems to spool about 150rpm faster than the 321T, but Kenny was using more Meth than Steve so probably very little in it.

There have been a few threads over the recent months discussing this type of choice. One that may be of interest:

https://www.scoobynet.com/scoobynet-...or-md321t.html

so the difference in hp between the turbos is upgrades made before or when the billet was fitted, not something simple like adding meth.
thanks
Trev

Hi Trev,

Difference in the maps is going billet , meth (from 5ltrs to 10ltrs) and map sensor.

All of these do help but the billet over previous version is very good.

I'm sure even on a MDX321T on a WRX non avcs etc a MD321H or a Sc equivalent would be best suited.

Also interested in this !

I have an H on my forged 2.5 with wrx heads which runs 441hp/480lbs, this is with 20%meth, it does start to run out of puff around 6k though. I have a billet T waiting in the wings which I'm going to fit Feb/ March time and hoping it will give a lot stronger top end.:thumb:
Trev

Did you consider putting a billet wheel in the 321H?
Not the smaller billet wheel and housing (better spool, same top end) - £450+vat, but a billet wheel in your existing housing - £295+vat (same spool, better top end).
I'm pondering this at the moment, on a 2.5

my engine spec;321mdxt less than 1k ago(lateral performance)dv deletedalcatek with anti lag fitted and mapped by jgm less than 1.5k ago.(417 v power 440meth)3 bar map sensor3 port solinoidperrin inletgt spec headers and Harvey smith up pipe. All heat wrappedjapspeed fmic255 fuel pump650 injectorsfuel lab fprcdf billet fuel railsrcm fuel lines and connectorsks tec mega maff induction kit with fog cover cold air feedfull 3" turbo back system*
my results
Attachment 57138

Hi I like to now the difference in spoolup between a md321t and a mdx321t the rpm difference on a 2.1l stroker.
And what spoolup can I aspect with a 2.1l stroker and pgw tmic and 850 injectors and invidia equal length header and sti type-r heads.

Hi there

We are run MDX321T on 2.1L and we are made 452bhp on V-power and on 20% meth we are made 490bhp

You should be able make 450bhp on yours spec,although yours TMIC can be limited factor,hard to say,you will see

MD321T non billet will always spool bit later than MDX321T Billet

Hope this helps

Thanks,Jura

I bought a new md321T for my 2.1 CDB classic I was told to go for the smaller h model as lateral recomend this T version on 2.1 only with avc heads on their site
But it spools like a mad thing I couldn't be happier
Also at the time I bought billet wheel was std and ceramic exhaust housing too
Don't know if this still applies
Really glad I wentvwith the larger one should easily make my 400+ target

Did you have a fmic or a tmic?

Newage topmount

Hi there

Personally I loved MDX321T on our wagon and has been good suited turbo for 2.1L

MD321H is great on non AVCS heads or for WRX 2.0L where this turbo making good power too

If you don't have billet,then I would go with billet upgrade there,MDX321T on yours 2.1L should make easily 450bhp and on meth I would be surprised if will not make 480Bbhp+

Thanks,Jura