Saturday, 17 February 2007

Running out of things to do!

There's not much I can do now until my chassis arrives. I finished building up the other driveshaft and fitted the remaining needle roller bearings to the other lower rear wishbone.

I'm not going to build the diff up yet as I need to trial fit it to the chassis to work out what shims will be required between the diff and the lower wishbone pivot shaft bracket. The shims need to be spot on to ensure that:

a) The pivot shafts fit through the brackets on the chassis

b) The rear toe in is correct (how much the rear wheels point in towards each other)

c) The line thrust for the rear axle is correct (the direction in which the rear wheels will propel the car - hopefully straight doen the middle of the chassis)

This will be much easier with the diff on it's own rather than having all the bits attached. The jag rear end could be considered a little complicated and I keep mentioning various bits and pieces that make no sense to the majority of people - so here's an exploded diagram to give you some idea (click on the picture for a larger image).

Desperate to do something I thought it would be a good idea to calculate what shims will be required between the rear brake disc and the differential output shaft in order that the brake disc will be central (within 15 thou) within the caliper - see photo below:

I did this no problem on the nearside calliper - but when I went to have a go with the offside calliper I found the bolts wouldn't go through the calliper - in fact the holes seemed about 20 thou too small! Plus when I checked the brake disc (had to wedge the calliper in place as the bolts wouldn't fit) the disc was too far outboard which could not be corrected by adding shims?

A quick call to Ed at Ward Engineering resulted in the mystery being unresolved - he is however organising a replacement calliper.

So that's about that - I can't think of anything else I can be doing now - other than making sure I've got everything I need to progress when the chassis arrives - my fault as I have obviously overestimated the amount of work required to get to this stage!