Transaxle Delivery

The Transaxle arrived today. It isn't just any transaxle. This one is a manual 7 speed, model 991. It is the same transaxle found  in the current production Porsche 911s. As far as I know, my GTM is the first one to sport this transaxle.

Shipping crate dropped on the Northern Man Cave floor.

This journey began March 2013. I am writing this in November 2013. I responded to a post of the Factory Five Forum (a place I have been too busy to visit over the past several months). A couple of phone calls later, we settled on a deal to purchase the 991 transaxle, plus clutch, pressure plate, fly wheel, mating collar and modification for inverted operation. Basically, this is an all in one deal designed to handle the 525 HP ls376/525 slated to end up mated to the 991.

This the normal configuration for the 991. In the GTM this is inverted. Note the blue drain plug and the shift markings.

Gbox LLC is a small shop in Boulder, Colorado. They deliver what they promise. The transaxle comes backed in a custom built shipping box. There is plenty of padding to keep things from banging on the way from Boulder to the Northern Man Cave. The top is screwed down. The best thing about this shipping arrangement is there is no shipping pallet to dispose of.

The 991 tilted on its side. The shift lever is in the middle of the transaxle. The black circle on the end is where the transaxle is bolted to the frame.

The current build site is very limited in space. Even though the engine will not be purchased for a while, it is necessary to get the transaxle into the chassis. My friends Matt and Gary came by to help me get the transaxle into the car. Normally, you take the body shell off the car to mount the transaxle. It turns out the opening under the engine bay in the chassis is big enough to slide the transaxle into the chassis. There is approximately 2.5 inches clearance. The lack of an engine is the only way this works. Again, I'll repeat the recommendation - put off the engine purchase as long as possible.

Mating collars for the 991 and an LS block. This is a custom piece. You can see the GBOX Logo at the top of the photo.

We positioned the 991 vertically with the bell housing flat on a plywood sheet on top of a dolly. We rolled the transaxle under the lift and eye balled the location to be approximately under the opening in the chassis. (B TW: Rolling the transaxle on a dolly is a lot easier than trying to find a grp on this beast and manhandling it anywhere.) We lowered the lift until it was just above the top of the 991. This means the bottom of the lift is a little more than 2 feet off the floor. Gary climbed up on the lift so he could give us a visual looking down through the hatch. I got on my knees so I could get a visual as the lift came down. Matt watched it from another angle.

Clutch already bolted to the pressure plate and fly wheel.

I brought the lift down really slow. We made a couple of minor adjustments (and we needed all sets of eyes on the transaxle to make sure we didn't do something bad). I got the bottom of the lift about 3 inches off the floor. This leaves the transaxle about halfway up to the cross member where it is cradled in the chassis.

Fly wheel. I so glad I just have to mount this in place.

Earlier, I measured the transaxle cross member and the opening on the transaxle bracket. It turns out the 991 needs an opening of 3.5 inches, and my bracket only has 2/75 inches. The transaxle bracket is the removable piece that can be swapped out between aither the Mendeola SDR or the Porsche G50 transaxles. The 991 is different enough that the bracket needs further modification. Last summer I jad the Vraptor pieces welded in place for the wing. I removed the bracket before the guys arrived to help. This made it easier, because this all comes down to brutal force to get it mounted.

These are the tabs that the transaxle needs to bolt through. They have to be cut out and moved so the inner diameter is at least 3.5 inches. When I dropped it off at Crystal Welding, I explained the situation and we agreed on the technical measurement of a smidge over 3.5 inches for the inner measurement.  

Now it gets tricky. The three of us looked down through the hatch at the transaxle. It is sitting there and it was kind of a Now-What moment. I clambered over the edge of the hatch and first stepped where the engine mounts reside. Matt leaned over the back end of the body shell, and Gary helped find things as we needed them. He thought about trying to heft it up. In the end, I tipped it backwards on the cradle. We had to be extra careful not to damage the drain plug. So I ended up standing on the dolly - this proved to be one of those dumb things that worked out okay.

I couldn't done this without these guys! Matt and Gary did a great job!

Matt held the back end of the transaxle, Gary had the 2x4 wood blocks and straps ready, and I tilted the 991 towards the cradle. Unfortunately, not only did the 991 move, but so did the dolly, the plywood sheet and my feet. I kind of did the Fred Flintstone run in place under the lift with a 200 lbs transaxle in my hands. Fortunately, we had enough leverage and the transaxle moved (relatively easily) into place. The dolly eventually slid out from under me and I was on stable ground. We strapped the and braced the transaxle in place, declared victory and congratulated each other on a job complete.

Here she is strapped and braced in place. I should have the transaxle bracket back in a couple of weeks, then she will be bolted into place until it comes time to install the engine.

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