Drive Train - "This is getting annoying..."
Original Setup
The car came with an M21 bolted to the 308, with a standard prop and V8 rear-end with a cone-type LSD, running a 3.33 ratio. It soon became apparent that M21's aren't up to the task (certainly not in stock form) to handling the output of a mild 308. So we bought a Toploader and mated that to the 308 via a Dellow bell-housing. While we were at it, we had half the synchro teeth removed, making the shifting easier (as a trade-off with faster wear). A custom clutch and drive shaft completed the conversion. The only significant problem we had with the Toploader (aside from it whining a bit when we forgot to fill it with oil one time) was the shifter. The shifter gate box would get filled with crud during the course of a race and it would soon become almost impossible to change gears. It became another maintenance item to oil the shifter box before each section of a race.
Just a small note. The difference between fitting a disc and drum axle on a Commodore back-end is quite small, however the two are definitely not interchangeable. The following pic shows why this is the case...
Rear-End Upgrade
With the breakage of many axles it became apparent that the stock VC rear just wasn't good enough. So we went to a HQ 1-tonner unit with a Salisbury LSD centre. This gave us a wider track, the larger axles and an LSD (which is good for distributing axle loads and stopping the things breaking). While we were at it the shock locations were also revised (see the Suspension section).
Two things became apparent: Firstly, the larger axles were no guarantee of less breakages. Whilst it is entirely possible that during the life of the car we were pushing it harder and harder, it was very evident that even 1-tonner axles are not up to the task. Secondly, the Salisbury LSD, being a cone-type, is not a good race part. It was always going to be a regular maintenance item, however there didn't seem to be any particular pattern emerging as to when the rebuild should be done. The first unit lasted 6 races (before a rebuild), the second install lasted 3 races (before dying), and the third lasted a single race (before dying). What was even more annoying, was the rather unfortunate effect of losing all drive when the thing died; as opposed to other LSDs that simple turn into an open centre. Admittedly, during the time we were running an LSD, we never broke an axle. Anyways, when it became obvious that the LSD wasn't working, we dropped a full-spool into the centre and locked everything up. This had some not so subtle effects on the track (that we were prepared to live with), and was simply annoying off the track. Never-the-less, the quad-cam mated to a 4.44 crown/pinion was a nice combination. Unfortunately the axles kept breaking... and breaking... and breaking... and then the pinion went...
The remainder of the season ('05) was spent working out how we could graft a GQ Patrol diff into the car. This never eventuated, and currently it still has a busted centre in it.
