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· Registered
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Discussion Starter · #1 ·
Like the title says. I'm going to be reinstalling it into my new CJ-6 project and plan to turbo it. I have a turbo from a 2.2(?) suburu that I picked up at a swap and was thinking of trying it out. I probably won't be able to run much boost I'm sure but I figured a few pounds would help out on the hills a little. The motor worked great otherwise in my CJ-5 but just looking for a little more get up and go.


· Super Moderator
9,630 Posts
There are some internal differences between the 4BD1 and the 4BD1T. The T has oil squirters under the pistons, but the pistons are also different. I mistakenly got sent some NA pistons when rebuilding my turbo engine and found they're about 4mm taller.
Compression ratio is the same in turbo and non-turbo engines.

Where this 4mm is made up again I do not know, logic would suggest a taller deck height on the block.

I have heard of people using WRX turbos with good results, but personally I feel the T25 is the best (and probably cheapest) option.
If you get the exhaust manifold from a 4BD2 then anything with a T3 flange will bolt straight up. It maybe possible to get a complete manifold and turbo from a blown engine, it seems the 4BD2's give some head trouble.

The factory turbo for the japanese 4BD1T's was an IHI-RHB6. Basically a japanese T3. Stock boost was supposed to be about 12psi, they blow 19psi with the wastegate held shut.
Export engines had a version of a garrett T25 on them Some pictures shown them wastegated, others not.
The 4BD2 turbo was a non-wastegated T25 with a T3 mounting flange.

Search through here:

Aussie landrovers were fitted with 4BD1 engines in the late 80's. Many guys there have turbo'd their 4BD1's.
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