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4 speed bus to bug 091 gearbox.

Posted: Mon Sep 14, 2020 10:47 am
by Passatman
Good day Bruce/Anybody,

Can anyone tell me what is needed to build a strong 091 gearbox for possibly a 400whp - 500whp turbo oxyboxer engine, what modification is needed on case, gear carrier and diff. I have a cone style LSD for this gearbox i intend to use.

Re: 4 speed bus to bug 091 gearbox.

Posted: Sun Oct 11, 2020 9:15 pm
by baja5
For 400-500 hp your 091 will need to be upgraded to a Mendeola or the equivalent trans. Even the full Weddle geared ones are only good for around 300. A full built 091 runs in the 4K range, and Mendeolas can regularly be found for 5-6k.

Re: 4 speed bus to bug 091 gearbox.

Posted: Tue Oct 13, 2020 6:10 pm
by Passatman
Oh, Well a couple years ago a friend of mine told me about an 091 bus box that was coupled to a 3.6ltr or it could have been a 3.8ltr porsche engine with 360 HP the friend told me the owner of the vanagon was dead set on distroying the 091 which didn't happen.

I think this can be done Marco Mansi did it with his turbocharged waterboxer beetle with 400 plus wheel horsepower a couple years ago.

Re: 4 speed bus to bug 091 gearbox.

Posted: Thu Oct 15, 2020 11:46 am
by Dougy Dee
Started into one a year ago.

Call Dave Folts.
You need the proper Bus to bug gear carrier (now back in stock).
HD (ie Weddle), Mainshaft and 3-4 gears.
Modified/clearanced main case.
trimmed/clearanced 1-2 shift fork
Shortened 1-2 shift rail
Shift rail shift fork locating slots elongated to accomodate the bolts
Weddle MD2D-820 Reverse Pivot Block
and 3R4M-1540 Fine Spline Reverse Gear
ANd whtever diff/spool that will work with your chosen R&P...

Good Luck

Re: 4 speed bus to bug 091 gearbox.

Posted: Thu Oct 15, 2020 1:26 pm
by Passatman
Thanks a lot dougy for the information. I did call dave sometime ago but that was about his 5 speed unit i was hearing about now that that unit will not be done anytime soon i am looking to do a 4 speed unit.