17 June 2000

The crankshaft, flywheel and pressure plate came back from the balance shop but the connecting rods are still out - engine assembly will have to wait a while.

The crankshaft was balanced by R and R machine here in Phoenix - very cool place, I recommend them to anyone wanting machine work done on water-cooled engines. This is what the crank looks like now that it has been turned 0.010" under, balanced, had the oil passages chamfered, journals radiused and micropolished.

Here's a closeup of where the balancer had to weld the crank to add weight:

They use a pretty cool dynamic digital balancer to accurately balance the crank. It suspends a rotating crankshaft on two bearings with built-in electronic strain gages and sends the data to a computer along with rotational position to determine where the crankshaft is out of balance. Then the crank is drilled to remove weight or welded to add weight. After the bare crank was balanced, the flywheel was attached and balanced, then the pressure plate was added and balanced. Doing the balancing in three separate steps like this allows me to replace the pressure plate without having to rebalance the whole engine.

Tatum Motorsports needs the engine/adapter plate/ transmission assembly to make the correct mounting brackets. The frame buildup starts in a week and should take less than a month. I won't have time to assemble the engine before they need it, so I'll just tape up the holes in the engine block to keep dirt out and send it over to them with the transmission.

I've decided to use a type 2 volkswagen transaxle - i.e. a vw bus tranny. It's been built pretty well and includes close ratio 1-4 gears, 4.56 ring an pinion, super diff, steel shift forks, hardened keys, stub axles for porsche 930 cv joints, blah blah blah. Here's a pic:

The fit of the adapter plate to the engine is fine, but the transmission was a bit too snug a fit. There is a machined groove on the adapter plate that fits into the transmission right here: I've got to remove the paint from the inside of the transmission bell housing where it mates to the adapter plate. Got out the old die grinder and went to town:

After just a bit of grinding the transmission fit perfectly, so cleaned out the metal dust and bolted the adapter plate to the engine: Then I bolted the tranny to the engine:

That's what the powertrain for the sandrail looks like, less heads, carb, header, etc.. the whole assembly is heading to Tatum on friday and I won't see it again for a month.

The cylinder head should be back from Racer Walsh sometime next week, I'll go ahead and post some pictures when it arrives.

Here's a shot of Mike sandblasting his axle tubes: