Planet-9

4.0 conversion for the 987.2 Cayman base?

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YOUR RESEARCH4.0 conversion for the 987.2 Cayman base?

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Run fully forged internals, dry sump and electric water pump

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I would also like to run fully forged internals, dry sump and electric water pump.
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4.0 conversion for the 987.2 Cayman base?

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Run fully forged internals, dry sump and electric water pump

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I would also like to run fully forged internals, dry sump and electric water pump.
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4.0 conversion for the 987.2 Cayman base?

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POST 1Original post

Hello everyone, I want to preface this by saying I'm new to to porsche space, a lot of the things I say may be wrong, please feel free to correct me. I came from messing with 2jz's and SR20's, where parts and rebuild guides are readily availible. I am stumped when it comes to any information on the MA1 engine. So just how realistic is stroking + boring a 2.9L base Cayman engine to a 4.0L? I can't find any stroker kits online, which means the crank, piston, and rods have to be individually sourced (unless you guys know where to find a kit), Can parts from other MA1 engines be used to make this work or custom parts have to be machined? Has anyone done this before? I understand that all factory 4.0L MA1s from porsche are direct injection and their coolant/oil passages have been extensively redesigned since the 987.2 Cayman . Will I run into fuel/oil/coolant issues if I do make the 4.0L conversion? I would also like to run fully forged internals, dry sump and electric water pump. Do you guys know where to source these or if they have to be custom desgined as well? Note: budget is not an issue, I'm just curious about the feasibilty of the engine I just described. Thanks!

POST 2Original post

Great question; I haven't seen/heard anyone do such a drastic overbore. I'm wondering if your best bet might be to swap out an engine with larger displacement, as I think people have done that before on a 987 -- you may have more luck in looking for that sort of thing. FWIW, I drive a 981 with a 3.8 (991.1S) engine and it's fantastic; no overbore; I've got both power and ridiculously great handling. Again, YMMV.

POST 3Original post

You can’t bore out a 2.9 to a 4.0. You really can’t do that with a 3.4. I think a few have but the tolerance is too close. 3.8 is the most you can reliably go. I’d get the 991 Carrera S motor, puts you in the GT4 arena. Your 2.9 is worth a nice chunk, so yank that and find a motor. BGB has done this along with a few gents

POST 4Original post

There is one for sale on this web site, P9. Its produces 836 HP and has seen numerous dyno tunes. Dry sump and all. Diverdog. $35,000.

POST 5Original post

Saw that… man that installed is sure to beat…. Everyone!!! 😂

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