which turbo for around 400bhp semi-forged 2.5
 

so im looking for around 400bhp give or take 10bhp from my hawk sti

it has....

2.5 built by scoobyclinic with closed deck inserts
mahle 2618 pistons
std rods with arp rod bolts
new crank
new acl race series bearings throughout
cosworth headgaskets
assumed 11mm arp head studs
rebuilt heads with upgraded valves/springs and retainers
engine has covered 8k @ 351
ran on royal purple oil since build with 2 x oil changes so far

other modifications are....

hybrid vf43 from cr turbos
japspeed fmic
scoobyclinic induction kit
full decat with 2.5 inch exhaust and vortex backbox
std headers and up-pipe
denso 750cc injectors
walbro fuel pump
extreme lightweight flywheel and ap racing clutch

looking for a suitable turbo to reach around 400bhp, though about the sc42 but quite expensive @ nearly £1800

any other suggestions?

cant run massive amounts of boost due to rods being std, also car is a fast road car only-no track work

mdx321h for 400bhp or buy 321t if planning to change rods in future

Already discussed rods on another thread buddy, won't be changing them unless engine decides to **** itself.

Mdx also a expensive turbo though, I'm sure there are blowers out there for around 1k that will do the job. Will speak with Owen developments and also engine tuner about their t36 unit

Scooby Clinics SC42 would blow on your car nicely:thumb:,im a big fan of SC turbos:D.....pricey but worth it for thier reliability and quality.SJ.

Plus1 here for the sc42, that good I'm going same route again.

i am running an owens development gt2860rs turbo in stock location at 1.65 bar of boost on my 2 ltr engine

Shrek my mate had a t36 turbo 2 years ago on his Subaru he was always raving how good it was....until it crapped itself at 410hp pi55ing oil out all over the place:( he now runs a SC42.SJ.

Gotta work out if the sc42 would be 600 quid better than the t36 from engine tuner as they come in at around 1100 smackers and offer between 380-450 bhp.

Also forgot to mention that I will be changing the headers for either ported as performance sti ones or a set of rcm ones if I see a set at a decent price.

Thanks guys

Hhmmmm not good

How about td05 18g?
I picked up my Andy Forrest version for £500,its making 380/380 at just under 1.5 bar on a 2.1,with slightly better fueling it could have squeezed a little more out.
So could get you just under the 400 mark on your set up.
I don't think you can beat it for bang for buck.

I thought the t36 was out of production due to not getting the Tweeks sorted.
You may want to change exhaust to a true 3" and some better headers and a Harvey uppipe.

And you can't beat the sc42 as the drivability is awesome, and I think I was at around 440hp on my last map.

This video was when I first fitted it and without avcs working and at just over 400hp at the time, few Tweeks needed to finalise it after some issues but just look at how quick it flys round the rpm gauge.

It's a 3 inch decat going to a 2.5 center section so will get that changed. What sort of boost would be I be running on an sc42 for around 400bhp?

Around 1.6/1.8 bar with supporting mods i.e right size injectors/fuel pressure,uprated fuel pump exhaust manifold up/down pipe exhaust etc....should see you there ,but remember no two cars are the same.SJ.

Just read your first post on this thread,with the mods that you have already your practicaly there mate.SJ.

have you a graph available?

just gonna put a fresh pump in and a fuel lab pressure reg and change the center section/headers

now then forgive me if im wrong but that seems a lot of boost to be running on the standard ecu and my std rods. i was always told to buy the smallest turbo to reach my goal so maybe an sc38 would be a better choice over an sc42 as i wouldnt be running as much boost then and still make around 380+bhp.

still learning all this mumbo-jumbo so again forgive me if im wrong

Agree, 1.5-1.6 should see you at 400, 1.7-1.8 is the most the turbo likes so dependant on engine, flow etc will reach over 420.
The drivability is awesome, makes a excellent point to point car or rapid daily (if I didn't want that so much I'd of chosen a bigger turbo like I was going to do, but it just wouldn't be as Rapid as that, so lower hp is sometimes faster on the right roads).
On your 2.5 is will spool way faster. May spin all 4s in 4th lol, mine span in 3rd on damp roads lol.

The lower boost, you can add more timing , higher boost is less timing, so say 1.5 bar and a nice amount of ignition timing will still probably achieve you more than 400, that's if all the mods and flow are correct

An sc38 will need pushing to get 400s, so more boost etc

right i understand now, im sure i read that the std ecu struggles with over 1.5 bar boost

yep makes sense now, thanks buddy :thumb:

Your right to fit the smallest turbo for the job but for your engine the SC42 would be perfect,the smaller the turbo "SC38" the more boost pressure you would have to run for the same peak power of the SC42.SJ.

:thumb:

or if my balls were bigger i could run an sc46 for more oompf, seen quite a few threads were people have ran an sc46 on std rods @ 440bhp.

sometimes i wish i was on drugs/beer as it would seem easier than this lol

Thats why on my car I can run under 2bar on my GT3582R and still have over 600 bhp:thumb:.SJ.

Red line on this graph is low boost @ 1 bar
Blue line is high @ just under 1.5 bar

https://cimg2.ibsrv.net/gimg/www.sco...c62af13254.jpg


Looking at the boost graph it looks like its actually just under 1.4 bar.

https://cimg4.ibsrv.net/gimg/www.sco...e09a2e56cc.png

fekking show off

My MD321H ran 420hp at 1.4 bar and 440hp at 1.55 bar, that's with 20% meth on a 2.5 with wrx heads.
A SC42 or 321H should get the high 300's at 1.4-1.5 bar on straight fuel.
Trev

:lol1:.SJ.