Welcome, Matt,

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Another option would be to run a complete longblock from a vr4. This has a lower compression ratio and would allow for more boost and ultimately more HP but it would be from a transverse mounted car and the upper plenums would give me issues.


Use a Montero 3.0L 24v DOHC plenum if you're concerned about the thermostat housing location.

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1. Has anyone done this yet?


No - not that I know about.

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2. Has anyone done a SOHC 3.0 to DOHC 3.5 swap in a Gen1?


No, but OldColt (Charlie) has installed a 3.8L with reworked 3.0L DOHC heads in a Gen2.

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Here are my potential issues:

1. Oil pan clearance with the front axle (4x4)
2. turbo clearance using the stock vr4 exhaust manifolds


Both are legitimate concerns, but there's likely a way around if you want to do it badly enough.

Here's my solution to the power question, but it's still evolving:

[Linked Image]

If the parts ever present themselves to me at a reasonable price, the next one might be a 3.5L block stroked with a 3.8L crankshaft and a blower.

Good luck and post some pictures of your progress.

Frank