It is much easier to flip the transaxle to get the proper drive direction then to flip the ring gear. The porsche engine is behind the transaxle and the GTm engine is in front, hence the need to flip it over so you have 5 forward 1 back, not 5 back, one forward.

 

I've heard a number of people say this is not right for proper lubrication. Others say it help you lower your center of gravity.

Mike

 

Originally posted by Michael Stora:
I've heard a number of people say this is not right for proper lubrication. Others say it help you lower your center of gravity.

Mike

it has to be modified a bit but I don't believe it affects the transmission.

 

Knowing that reverse rotation crankshafts and camshafts are readily available in the boating industry, would that solve the problem rather than flipping the trans over?
Just wondering out loud, since marine applications require you to specify clockwise or counterclockwise rotation (on boats with twin screws) or at least they used to a long long time ago when I worked in that industry.
mannyjoe

 

I did a quick search on google, and most sites indicate that the G50 ring gear cannot be flipped. However, there seems to be alot of folks running them inverted with no issues.

 

That's really cool to know. I'll most likely do a cobra build since it seems much easier and is cheaper. However, it is amazing that you can run the transaxle upside down with no problems and only minor adjustments. Guess that's why the 911 series engine and tranny have really changed very little in basic design for almost 50 years.

Sooner Builder

 

Originally posted by SoonerBuilder:
That's really cool to know. I'll most likely do a cobra build since it seems much easier and is cheaper. However, it is amazing that you can run the transaxle upside down with no problems and only minor adjustments. Guess that's why the 911 series engine and tranny have really changed very little in basic design for almost 50 years.

Sooner Builder

No, it's because Porsche is stubborn.
I have a friend that is one of the head engineers at Porsche, he likes to say; "Porsche, a bad design engineered to perfection."

 

From what I understand of the construction, upside down puts the syncros out of the oil bath. Running a bit more oil in the box gives you more splash to keep them lubed under high loads.

The basic trany has been used for years in GT40 and Ultima kit cars without problems. Some will use pressure spray bars on the syncros, but that's overkill for anything less than ~500 ft-lbs. (so they say...) If you're planning on running enduro or something, you might need to do spray bars as well, but then you'd be better off buying a Porsche RSR or something if you're gonna race.

 

So all it took to make this transmission work was to flip it over? There were no internal modifications needed to make the gears work?

 

Nope.

Some have fitted a breather kit since it's now on the bottom. But that uses existing fittings.

 

OK, so how do you PULL the tranny in this? I have am having a heck of a time....any tips to get it moving backward?

My problem is the shifter fork shaft....won't seat the bearing at the far end, I think I need to see what is binding up (stupid me did dry fit before now....).

Jon

 

Every thing you wanted to know about Porsche transaxles is at Renegade. Great site http://www.renegadehybrids.com/main.htm

 

Got it.....but ours have the adaptor plate, etc....has anyone pulled the G50 off?

Also, I have a G50-52. Its about an inch longer than a -50 or any of the -0x (01, 02, 05, etc) tranny's. That means 1) the rear tranny support doesn't fit to the donut....gotta weld your own tabs, and 2) shifter linkage too small.

I am trying to get FFR to send me a rear support without tabs or powdercoating (I will send theirs back) and I can weld the tabs....beats grinding off what they did, which is messy and takes time. In return I will send them the dimensions for the -52 welds. Hopefully they'll do it. Jason wasn't sure when I called today.

Jon

 

Does anyone make/sell a vent kit/puke tank for these to take the place of the drain plug?

 

Jon,
I pulled my G50 back off in order to put in a new engine. Just pull the clutch fork rod back out by inserting something that will fit into the hole on the end. A small rod, allen wrench, screw driver will work by applying a little side pressure and pulling it out. The release fork will then let go and the tranny should just pull back. What I found was that it needed to be at the correct angle in relation to the engine and it slid backwards.
Allan

 

Mine's a b&^%$ to move backward. Turns out my clutch fork rod won't go in ALL the way....I think I have a burr in the far casting. I am going to insert a reamer where the fork shaft goes (7.56 inches is the measure) and clean it up in place rather than pull it off. Arghhhh. I should have fit it up on the bench....

BTW, the fork rod is threaded on the near end....you can insert a bolt into the rod after removing the dust cap and easily pull it out...

Jon