The daily Post

With only 2 weeks left till the first race of 2010, and there still being jobs that are needed on the car like

• Alignment
• Finish off the rear trailing arm bush (the one with the snapped bolt in)
• Lighten the car as much as I can
• Fit new clutch
• Tidy up the electrics and attempt to put on a coil on plug kit
• Locate a new supplier for the tow van, as last years supplier has none this year

As the above list keeps growing, some items are going to have to be delayed, like the clutch, as it should last for the first race at Brands Hatch.

Other items are not in my power to do like the alignment and removing the snapped bolt, so the car is going to get transported to BM Sport where Jags is used to snapped bolts, as he does it himself on a regular bases.

From what I could lighten I started this weekend on the bumper supports, there are fibreglass mounting structures behind the front and rear bumpers that can be reduced in weight, by drilling circular holes in them (had to buy a hole cutter drill bit) and you can also remove the ends of the bars, all aids to save about 2.5kg’s per end of the car. The only problem that I encountered was after drilling about 7 holes, my drill ran out of charge, no problem you may think, but when I put the battery back on charge, it would not charge, so I can not finish the holes in the bumpers, although I did get the grinder out with a cutting wheel on and chopped off the outermost parts of the bumper support, and so far (not finished) have removed about 2kg of weight from the front bumper.

The electrics are waiting on a connector block to be sent from the suppliers.

The tow van has been sorted and I should be renting the same van for the coming season, so at least one thing has been done.

I got up early on saturday morning to finish off what I had started the week before (replacing bushes on the rear axel), and now armed with a 1/2 drive 18mm socket I thought it would be easier going this week.

I had changed the rear track control arm (RTAB) bush the weekend before, but had not finished with the top ball joint, (as I was waiting on the part to arrive from BMW). Also the week before I had noticed that the anti roll bar drop links were well past there sell by dates on both sides, so I removed and replaced these whilst the car was in the air.

Then I hit a snag, I moved around to the drivers side to do the top ball joint, no problems, and then started to remove the three bolts that hold the rear track control arm bush holder to the body of the car, one of these snapped clean off (as you can see in the photo) and it left me with this as an issue. A couple of places that I have spoken to have suggested leave it as it is, as two will hold it securely, but for piece of mind I think I want three bolts holding the carrier in, as the car is being used for racing, so when I can get the car down to BM Sport they will get the rest of the bolt out, and do the alignment on the car, so at least I can get to the first race.

I think I am going to have to leave the clutch to be done in-between the large gap in racing that we have during may and june, as it would be cutting it very tight to get this done for Brands on the 17/18th of April.

UPDATE.
Jags at bmsport (http://www.bmsport.com) removed the bolt with skill, he drilled the center of the bolt with increasingly large drills, until he could get some special tool into the center of the snapped bolt, then with a little heat it was out.

Well I tried to change the bushes on the rear of the car, I started with the top wishbone bush, as I had brought some of these from ebay earlier in the year, to ensure I could remove them easily, I had brought the proper tool, this helped a lot, and the existing bush was removed easily.

To put it back in the tool has to be dismantled and reversed, so I began to do this, and assembled the tool in place with the bush in the center, but the bush just slid in, this was obviously not correct, so I have had to order another 2 bushes today from a proper BMW dealer.

Whilst I had the car in the air, I noticed the rear copper brake likes were starting to look ropey, so these are now scheduled to be replaced, and I proceeded to change the rear trailing arm bush (RTAB) and put in some powerflex bushes that I had brought from bmsport. One side went easily, the bolts were tight but they did undo and it was all reassembled and put back, then it was time to change side, when I started the RTAB on the drivers side, the first thing that I did was snap my extension bar that I was using to reach the bolts, so this is where it ended for the day, as they are 18mm bolt heads, I did not have the socket in my 1/2 driver set, so could not progress.

Will have to buy a 1/2 socket in 18mm and also will replace my (now broken) 3/8 extension bar, before I can continue with the bush replacements.

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.

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.

Afters last seasons racing I need to get the weight of the car down by about 100kg’s to be on the minimum weight (being on the minimum weight helps with my power to weight ratio, which should entail me being quicker). My wheels that I ran last season weighed 9kg each, these new wheels have a weight of 6.8kg each, so I get a saving of 8.8kg by using these new wheels. I got them matt black so the look of the car is unchanged, these weights are without tyres mounted on the rims.

Other ideas to shed the weight is to lighten the front and rear bumper carriers (although don’t know by how much that will lighten the car by), there is still some metal that can be removed from the bonnet and boot (but I think this is minimal), so the next weighty area that I can think of is the windows, swapping them for perspex, I have been told could free up about 10kg, but they are expensive, so before I splash out on the windows a little more research is needed to quantify what the weight saving will be.