What kind of gearbox to use on high power F6 ? Options

[speedsterms]

Hi all,
I leave in France.
I use to have some 911 (3.2l, 993RS Club Sport, 993 RSR, 993 c2)
today I am on another project : 917K Replica.
with a mid mounted engine - the reason why i am asking my question here-

My engine will be a high rev/high power aircooled 3.6l.

I have planned to mate the engine to a 915 gearbox with flipped R/P. but I was told by my mechanic that the 915 will not handle the torque. even if I improve oiling and cooling and add a wevo bearing retainer.

I had a G50 (which I swap to the 915) as it was not usable. impossible to flip R/P. and flipping the gearbox is not acceptable to the CV joint (too much angle) .

I wonder if any one of you have tryed to install a cayman 987.2 gearbox (G8740 to be precise, not the fisrt gen) on an aircooled flat6 ?

Is there any kit available ? (adapter plate)

[Charles Freeborn]

Hi all,
I leave in France.
I use to have some 911 (3.2l, 993RS Club Sport, 993 RSR, 993 c2)
today I am on another project : 917K Replica.
with a mid mounted engine - the reason why i am asking my question here-

My engine will be a high rev/high power aircooled 3.6l.

I have planned to mate the engine to a 915 gearbox with flipped R/P. but I was told by my mechanic that the 915 will not handle the torque. even if I improve oiling and cooling and add a wevo bearing retainer.

I had a G50 (which I swap to the 915) as it was not usable. impossible to flip R/P. and flipping the gearbox is not acceptable to the CV joint (too much angle) .

I wonder if any one of you have tryed to install a cayman 987.2 gearbox (G8740 to be precise, not the fisrt gen) on an aircooled flat6 ?

Is there any kit available ? (adapter plate)

Bonjour!
Lots of variables. I would say it depends on how much hp and torque the engine will produce, the use of the car (street/track/both) and how often you're willing to rebuild- refresh the transaxle.
For my money, the 901 tops out at 200ish hp. A 915 @ 300, a G50 can be built to handle several hundred hp. I know someone who built a GT40 replica that uses a flipped over G50 mated to a very nicely built 302 and it works fine.
Outside of those choices you're into the world of race boxes such as Hewland, etc, which can be bullet proof, but also may be dog boxes, etc. Fine for track but a bit much to shift on the street.
Clutch / flywheel adapters and combos can be had from Kennedy Engineering. Maybe transaxle to engine adapters too. I imagine they'll build about anything if you've got the budget.