the build

During the first race at Thruxton in 2010, my car and that of another competitors got a little close, ok they tried to go round the outside by pushing me to the inside of 'Noble' so what was left was a dented door, rear quarter panel, and all they got was a little wing damage, and the indicator lens broke.
Whilst the picture does not show the full state of the damage, but the rear quarter panel near the sticker is pushed in and the edge is pushed to the door, the sill has a small dent (that will probably never come out), but the most painful is the dent in the door (highlighted by the red paint). The tyre marks were just a mark, and with a little polish should come off without harming the paint underneath.
I thought about having a go myself, but just visioned needing to get the door resprayed, and the quarter replaced if I touched it, so I thought I would try one of the many dent removal companies that advertise the ability to repair dents without needing paint. As the one on the door had not broken the paint (the other dents had) this one was my main concern to get back into shape. After a couple of calls I got some estimates to fix the damage, and instructed one company Dent fix to come out and fix the dent. It was harder for them to do than expected as they did not realise it was aluminium doors (they are apparently easier to dent, but harder to straighten, as it takes more force to push them back to shape). After about 30 minutes of working on the door it was nice and smooth again, the rear quarter was also pushed back into shape as much as it could be (due to it being on a edge it could not be pulled back totally due to the inner constraints of the panel)

From researching on forums and asking questions of other drivers in last years racing one of the simplest ways of loosing some weight from the car was to have 'Aluminium' doors, these doors were fitted to some M3's at around the 1995/1996 model years, and from whats been said, they are the lightest you can get that are original BMW equipment, as we are not allowed to run composite doors, like carbon fibre or fibreglass.

I started to search for a pair of these doors last year, about November time, but most places had not heard of them, or if they had they wanted some serious money for a pair, it seams its not just racers that like them, people with later road cars like the doors also.

It took me till February this year to locate the doors, I got a drivers one in December of last year, but the passenger was harder to locate (without paying silly money)

I decided to do some experiments with the weight to see how much (if any) I would save, below are the figures

• Standard door (glass, impact bar but no electric motor for the window, as I had sold it) - 28kg
• Standard door (as above but with the interior stripped, and cut back) - 25kg
• Standard door (as above but no side impact bar) - 22kg
• Aluminium door (glass, impact bar, no electric motor) 16kg

So having them just fitted as they are I would aim to be saving about 15kg, as my drivers door still has the side impact bar in, this should take my weight down to 1140kg ish in race prep.

The door glass by its self weighed 4kg, and from what its been said about plastic windows, this could be cut down to 2.5kg (they state 40% weight saving), at present I think I may keep the glass in the doors, as it does not move around when racing, and i can if needed fit the electric motors and have windows that move, unlike now when they are fixed in position.

All I have to do now is get the doors sprayed white, as currently one is black (the original primer from the factory) and the other is a nice shade of blue.

Well after a lot of hammering and drilling the rear bushes surrendered and left the diff carrier housing, and have left space for some powerflex bushes to be fitted. Before this gets onto the car though I am going to either powder coat it, or spray it, powder coating would be more durable, but the one diff bush thats left in would have to be removed, if I spray it then this bush can remain in place.

I am torn at present as to which colour, as I have some 'Treehouse Racing' front bushes and these are in a lime green colour, but the standard colours under a car are black (satin) so should I go green or black.

I brought a second hand rear diff carrier about 2 weeks ago with the aim of removing the bushes, and putting in some powerflex bushes so I reduce the movement in the rear of the drive train, the first job though was to remove the 10 year old bushes, this is not a simple task, as BMW employ a special tool to do this (but at about £300), I thought it was a little too much money. So the old fashioned method of removing the rubber from the bush in a sufficient quantity to allow a hack saw blade in there, so that the outer metal of the bush can be cut through, and weaken the bush's hold on the diff carrier.

The first one got a little more mangled than the second one, but I think thats normal, as the second one is always simpler, I have another two to do before I can attempt to paint the carrier (lime green is my current thought on the colour), but items outside of my control stopped me removing the final two bushes. (it started to rain, and my battery died in the drill.

first bush: removed from carriersecond bush: still in carrier

Just another two to go, then I can paint it, I brought a spare one, so I do not need to have my car raised for the time it takes to replace the bushes in the rear diff carrier, and I am also going to change the rear track control arm bushes, but for this one I think I will purchase a special tool.

Yesterday I went and picked up a second hand diff carrier, so I can change the bushes whilst its off the car to some that are more suited to racing, I think I will get it powder coated also before I put on the new bushes, this will give it a clean look underneath.

Nothing much happening recently as its cold outside, but the car got its xmas present today of a new clutch, just need to fit it now.