A Corvair engine and a VW engine rotate in different directions.  Both are normally found in a REAR engine configuration, like the Porsche 911.  So when people installed Corvair engines int their VW Beetles, Buses and Dune buggies, they would end up with Four reverse gears and one forward gear.  Not the hot ticket.  Back then the VW aftermarket wasn't what it would later become and a Corvair was a cheap way to double the power with a trip to the wrecking yard.  Fortunately, the design of the VW swing axle is such that the pinion gear is right in the center of the case.  Since the side covers are both removable, it is possible to remove the differential and ring gear as a unit and install on the opposite side of the case. This reverses the drive of the transmission.  Now you have 4 forward gears again.  Well, the GS has the entire power train flipped into a mid engine configuration. Normally this works great with a Corvair engine and a VW transaxle - everything's running the correct direction.  HOWEVER, you are turning the drive gears (1-4) the opposite way that they are designed.  The ring and pinion gear is striaght cut - no issue there.  The drive gears are helical cut - meaning the helix or pitch of the gears causes them to be pulled together as power is applied.  This is good for strength.  When you turn these gears  in reverse, the helix is pulling them APART.  This is bad, say at 5000 RPM on an AutoX course when you are trying to change gears.  I have always had problems with the shifting of my GS.  

Now that I reversed the rotation of my engine with a special camshaft, I must turn my attention to transaxle.It must also be reversed by "flipping" the ring gear to opposite side of the case.


Here is the non ring gear side of the transaxle with the cover removed.  In Mid engine layout, this is the driver's side. 

Here is the differential and passenger's side cover all together but out of the case.  The axles are still attached and that makes it easier to handle.  It's hard to  see here but the ring gear bolts are safety wired.  There is also a special Crown Beryllium washer shimming the ring gear end play.  This was a trick to keep the diff tight so the shock load wouldn't kill it.  This transaxle was gone through when the car is built.  I didn't want to mess with it too much.  

Here is the transaxle case with the diff out.  Needed a good clean up. but the insides looked very good.   It's a 1967 unit.

Input shaft on left, pinion gear on right.  Teeth look nice, not all shiny.

Here is the back of the car with the engine and transaxle out.

Empty engine compartment.  


Rear view.  Z-bar and Koni Coilovers still in the car at this point.

Transaxle and Axle tubes ready for cleaning.

These are the Autodynamics fabricated Trailing arms.  I wonder if these are the same as on one of their Formula Vees?

Trailing Arms

Spherical rod ends at the chassis side.

Beadblasted Axle tubes.  These are the "long axles" I think they are 1967 Beetle only.

Beadblasted trailing arms.  You can see the intricate welding that went into making these.  This was before TIG welding, too!

Bruno was an artisan.

Beadlbasted parts getting up to temp in my new powder coat oven.

Transaxle cleaned and painted with Hammerite.

Rear of chassis clean up and painted with some Rustoleum.

Axle Tubes in Satin Black Powdercoat.

Rear trailing arms in Satin Black Powdercoat.  My go-to color.

I made this nifty tool to install the rear wheel bearings.

Driver side axle Assembly.  Red mounts of the Porsche 914 rear calipers.

Here you can the the HD side covers I installed on the transaxle when I flipped the ring gear.  They stiffen the case.

No shocks at this point, they need to be rebuilt as they were leaking.

914 Brakes.

Stainless Steel braided brake lines.

Shifter cables in place.  Next up will be a new bracket to mount them too,  I'm not mounting to the transaxle ay more, I want to eliminate the possibility of leaks.

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