Subaru Impreza STi VI - What rebuild to go for?
 

Have a 85k miles STi VI. The very last model from the classics. The engine finaly went last week. So I have a choice

1) Standard rebuild - same turbo, same block. Approx 310bhp
2) Standard rebuild - but different Turbo. Approx 360bhp
3) Go for a 2.5 rebuild. But then I think I need a gearbox upgrade to take the torque. Approx 400-440bhp.

Anybod else had a similar decision to make. Anyone advise on what parts I need for (2) and (3)?

I'm not a Subaru guy, but if you are going to dump a lot of effort into the car and it's not your daily driver, I would probably go standard rebuild with upgraded turbo. Unless you already have the gearbox and wouldn't have to purchase anything.

You can get a turbo for cheap - the gearbox would hit you hard though.

I love STis, I envy you!

what kind of money are you willing to spend? I think the bigger turbo will get you a lot more power, but at the cost of serious turbo lag. What about twin turbo-ing it a la the EJ20TT? But I guess that will put you back in the same place with the gearbox...

Think I'll go for an uprated Turbo.

Done some more digging on the 2.5 upgrade and it's the mega-torque that strips gears (2nd and 3rd). Putting a 6-speed box in the car solves the problem as it's much stronger. But in a classic shape it means also changing the rear diff too. I'm certainly not going to start spending that kind of money.

Thanks for the advice.

Good choice. make sure you throw some pics up here when you get it all squared away. :)

Yeah, I want to see the pix when you're finished as well! (wrx wagon owner here!)

Always build it to be faster, that's my motto. Definitely go for the six-speed, the five-speed gearboxes are like glass.

It's been a while since I've laid hands on Subarus, so I have no idea what's new with their stuff. Last scooby I had was a 2.5 RS that had no aftermarket support back then and importing a JDM engine was an arm and a leg, forget about trying to get a 22B engine.

If you're going with a big dawg turbo, make sure you bump up to a nice sized intercooler, injectors, fuel pump, and whatever they use for fuel control (but I'm sure you already know that).