Gen 4 Subaru Legacy Twin Scroll turbo required for around 450bhp on a 2.5L forged.
 

Hi guys,

I have 2007 facelift Subaru Legacy 2.0GT Twinscroll. Unfortunately, the bottom end has started knocking so I have decided to go for a forged engine build.

My engine builder and I have discussed and I've decided to go for a 2.5L which I think would be lovely on the road. Once I have all the supporting mods, I would like around 450bhp/ftlbs out of it.

I know there are a fair few turbos in this range for the Impreza but do they bolt up to a Legacy? If not, can I have some recommendations please for legacy specific turbos?

My car has the STI 6 speed manual so apparently, it has a TD05 turbo as standard. Is it possible or even worth looking at getting this hybrid-sed (is that a word? lol) to make more power?

Thanks
Anees

Hi mate,seen your thread on legacy forum.
it won't be a td05,it will be a vf series turbo.
you will need a twinscroll turbo from a legacy or an impreza .
if you go impreza I'm pretty sure you will need to get the matching impreza downpipe and maybe uppipe I'm not sure.
this is because the legacy downpipe flange and turbo flange are specific to the legacy.

Legacy twin scroll flanges / turbo set-up are odd ball in comparison to the Impreza variants............

as above you potentially have a (very small) TD04 (manual) or VF (auto) series on that car

Would it be possible to change the manifolds, up pipe and down pipe for an impreza version?

That might make sense - much easier to get Impreza versions of these, then from the manifold back I could have a custom system?

Ps. It's only an idea, I've no idea if it'll fit or work...

yes if the complete manifold, up-pipe, turbo was used and you would need to swap the downpipe flange to suit also............