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Sun Jun 03, 2012 4:22 pm

Has anyone fitted a P-car 915 gearbox into a Vanagon? The later 915 gearboxes from 911SCs should handle the power/weight of the SVX/Vanagon.

I have and SVX mated to the 091 VW gearbox. I love the motor, but the transmission ratios are just not suited to the SVX.
The motor is turning 3000 RPM at 60 mph with a .77 4th gear in my 091.

My other option is to buy a 4.15 R&P from Rancho and build a wide ratio 4 speed 091.

Mon Jun 04, 2012 5:41 pm

It has been done a couple of times. Ottmar's stretch Vanagon has a 915 in it hooked to a TDI engine. There are a couple things to consider about using the 915, though. First of all, it is set up for cable clutch actuation so you would need to either convert the Vanagon to work with a cable clutch, or modify the transmission to work with a hydraulic slave cylinder. I believe Ottmar did the latter. Secondly, you would need to use a lengthened 911 shifter to shift it if you don't want the side to side gear pattern to be reversed. Lastly, the 915 has really balky and slow shift action. Be sure to drive a 911 with one and see if it has manners that suit your tastes. A better choice, albeit more expensive, would be to use a G50 Porsche transmission from a 1987 and newer 911. This is a much better gearbox, and it is set up for hydraulic clutch actuation.

I'm just curious. Did you know that the Subaru 5 speed can now be used in a Vanagon? It seems like this would be the most logical transmission upgrade since it bolts right up to your SVX engine.

David

Mon Jun 04, 2012 6:19 pm

The other option is rubber gearing...less money :D
I find that 225/75/16's gives nice ratios with no issues
between 28.5" to 29" rolling diameter, (depending on brand) is ideal.
I have .70 4th and .77 3rd and with 200+ hp I'm into 3rd for hillclimbs at 65/70mph with passing power, and criusing in 4th at the same speed, on the flats.
...great gas milage in 4th 22mpg +

Tue Jun 05, 2012 3:46 am

I must say that converting a Subaru 5 speed is probably the most sensible approach. The Vanagon when powered with a modern motor, really needs'longer legs' in high gear, and also the gear below top gear needs to be fairly close for downshifting. The Subaru gearbox has both covered.

The 915 Porsche gearbox , when filled with the correct oil is actually a good shifting tranny, I have a bit of experience removing the poor shifting issues from a friend's 911SC- the problem is usually worn shift linkage parts, and the wrong type of gear oil. Using a good old fashioned GL-4 transformed his SC from just plain baulky shifting into a crisp shifting machine. The GL-5 synthetic was actually too 'slick' to make the syncronizer rings work properly.

Increasing the rolling diameter of the tires is the least expensive way to 're-gear' the drivetrain, and worthy of a second look. Your .70 and .77 top two gears is a simple approach, and the tall tires will sure fix the low ratio in 1st.
Hmmmmmm

Tue Jun 05, 2012 6:22 am

Thanks for the recommendation Camo Westy!

Check out the videos on www.subarugears.com
You can see how a Vanagon drives with a 2.5 EJ25 and how a Kombi drives with an EZ30 6 cylinder.

These are the perfect transmissions, matched to your engine by those clever Japanese guys that made it in the same factory.

David Clymer on this forum is preparing Vanagon Subaru 5 speed kits that will make it all simple to bolt in.

If I can send you any information just shout. Cheers!