As above, Ive just built a forged 2.5 to go in a V5 STI, it's running 2004 WRX heads and an 8.5:1 C/R, jut wondered what your thoughts are on turbo options?

 

This may help:

https://www.scoobynet.com/scoobynet-...hat-turbo.html

 

Well i can HIGHLY reconmend the SC46! I had it mapped conservatively to safeguard the rods and it made 440/400 on vpower and 410/390 on 95ron ..... and its sooooo feckin drivable and spooly!

for 400 on the nose though you could consider the SC42 which is also a ball bearing so youd get better spool but slightly less top end beans.

If this is out of budget, the SC40 is the largest sleeve bearing they do, has seen some good results too!

 

Another SC46 billet suggestions here. Absolute no brainer with spool and power characteristics on the 2.5

 

Andy,

Mines running an MS321x (V with smaller exhaust housing) It's one of your 2.5's as you know but STI AVCS heads of course! 440BHP but on std ported headers. I'll pop the graph up if you want.

 

for 400 bhp- MD321H//SC40
for 450 bhp- MD321T/SC46
for something in between- SC42

 

20G

 

+1

 

Funny enough i am doing the same next year, I think 20G. I would love to see a praph or two, was planning good power by 2800 rpm max.

 

SC46 on mine 1 bar by 2700rpm 470bhp/480lbs

It goes.....

 

Thanks for the input folks, He was looking at an MD, I suggested the SC range, I'll pass on the info and he can make his choice, should go well in a Classic )))))))))))))

 

2.0? forged?

Jay

 

The H would be running out of puff on a 2.5, easier to get 400 on a 2litre but not a 2.5.
Trev

 

Depends on compression ratio. flow rate, typical BHP is related to the turbo as opposed to the engine cc, as long as you are not well ouside the compression map of the turbo.