Bi-turbo turbocharger compatibility? - The Unofficial BMW M5 Messageboard (m5board.com)

lifewith34 · 15th September 2003, 07:50

I'm going to change my turbochargers and manifolds due to lifetime. I inquired about a price to a dealer, turbocharger is 3,400euro each and manifold is 1,600euro each. (How much in Europe?) Since there is a only one official importer NICOLE Automobile in Japan, we cannot import ALPINA parts easily. Therefore, I'm going to change my turbocharger to other one (not original) that can be fit bolt-on or less modification. I know garrett T25 is popular turbo and I can purchase rebuilt one comparatively cheap. But, I'm not sure which turbo has compatibility at shape and performance. I don't want to change to bigger one.
Does anyone know which turbo can be fit to Bi-turbo? I would be appriciate it if someone would tell me a details (garrett parts number, compatible car and so on...).
I'm in Seattle now for business. If I can purchase turbos in US, please let me know where can I order. Thank you!

Hollis · 15th September 2003, 08:59

The stock turbos are T25's, so you can just grab those rebuilt ones you found.

m5 killer · 17th September 2003, 01:04

stick with the t25 get your ones rebuilt not advisable to change as the ar on these turbos is 64 and that is big hence the top speed on the bi-turbo dont mess about with it.

lifewith34 · 19th September 2003, 09:12

Thank you all

I think buying the same spec turbo is impossible except for retail parts. If I purchase alike spec turbos, what should I regard with? For example, A/R of exhaust and compressor, inlet and outlet size/type of ex and comp, etc...

If purchasing alike spec of whole turbos is difficult, I'm going to consider buying repair cartridges. Has anyone overhauled bi-turbo's turbo at garrett dealer? I would like to know garrett parts number. Thanks.