1 Series (E87) Tarmac rally car build by Mefmotorsport

[mef]

No, I've not made a start yet Barry, I will get stuck in this coming weekend. As far as events are concerned it all depends on how quickly it comes together. I was thinking about Croft at Christmas as a possibility, failing that maybe Epynt next March but definitely Monteberg around about the 5th of May. There's not really much fabrication work to do having already done the engine mounts, just the cage, seat rails and sill jacking points to do so hopefully it should come together quite quickly.

Martin

[mef]

Slow progress I'm afraid this weekend. I've been weighing up the cage fitting and have found that it's certainly a lot more difficult fitting a cage which has ready profiled tubes than all the previous ones I've done before where I had to profile every end as I went on. This is because the lengths of the tubes are critical, everything interacts, theres no measurements supplied as a reference, the positioning of the main hoop is critical and has a direct effect upon the position of the front A bars etc. Looks like the only datum I can find are the rear shock absorber turrets, I think I'll use that and work forwards from there to define the main hoop position and then the A post bars. I need to get as much fitted in place as possible to make sure its the way I want it before I weld anything. So far I've tacked the main hoop in place so I can offer up some tubes and see where it all needs to be. Very time consuming, frustrating and fiddley! I'll get there though. I must say that where I have had the tubes in place, the accuracy of the profiled ends is superb.

Martin

[M3 Compact]

Slow progress I'm afraid this weekend. I've been weighing up the cage fitting and have found that it's certainly a lot more difficult fitting a cage which has ready profiled tubes than all the previous ones I've done before where I had to profile every end as I went on. This is because the lengths of the tubes are critical, everything interacts, theres no measurements supplied as a reference, the positioning of the main hoop is critical and has a direct effect upon the position of the front A bars etc. Looks like the only datum I can find are the rear shock absorber turrets, I think I'll use that and work forwards from there to define the main hoop position and then the A post bars. I need to get as much fitted in place as possible to make sure its the way I want it before I weld anything. So far I've tacked the main hoop in place so I can offer up some tubes and see where it all needs to be. Very time consuming, frustrating and fiddley! I'll get there though. I must say that where I have had the tubes in place, the accuracy of the profiled ends is superb.

Martin

Good luck.

I don't envy you the task, I can see why the pre-profiled ends makes it very difficult.

Great project.

[mef]

Still slow progress I'm afraid!

Spent a few frustrating hours yesterday unwelding 100's of spotwelds on more unused BMW brackets, we must have removed a couple of Kilos of steel! It's important to get all these bits removed now before I get the cage welded in place as it would make access very difficult for the drill in some places.

Having now spent a couple of weekends "pondering over it" I feel a bit more confident now with the positioning of the roll cage main legs. We fitted the rear turret locating tops and worked forward from there. Hopefully I will soon be able to tack it in place before dropping it down through the floor to weld the top joints.

Martin

[mef]

I finally made some progress over the weekend, I thought I'd give the cage a miss for now and do something else! I decided to fit the seat rails for the drivers seat. I found that positioning was very critical and not at all straightforward. Being a 4 door car the wings on the seat want to be in line with the B post, this means the seat has to be set towards the tunnel and leaves what seems like a big gap between the seat and the sill/door bars. That said, it lines up nicely with the steering column and positioning of the brake and clutch pedals. I Think the steering wheel mounting needs to be shorter, it comes out too close with the demountable boss, it's too close when I get the seat the correct distance from the pedal.

Talking about the pedals, I've been thinking about what to do for a pedal box. The problem is that the existing one is alloy and doesn't really lend itself to modifying for a pair of bulkhead mounted master cylinders. I was thinking of re-making it out of steel, using the existing pedals and pivots as they work nice. the alternative is a floor mounted pedal box but I'm not sure about them, what do others think?

Martin

[bruvs1]

never had floor mounted but went down this route in the compact , got these handy money from demon tweeks clearance, lets hope the work as good as they look!!

[hsr2.6]

What sort of pennies were they........

[ultegra]

If you have the skills and patience then pendant pedals are preferable rather than floor mounted but you know well enough that the fabrication is rather more involved.Floor mounted pedals ask difficult questions of your ankles; even Porsche ditched them when they bought out the 996.

I saw a nice car at Castle Combe that had fixed drivers seat with the 3 floor mounted pedals on a sort of rack that adjusted back and forth to suit giants and midgets alike. Not unlike in the old Jet Provost......

[mef]

Yes, I'm not sure I like the idea of the floor mounted pedal box really, all those hydraulic pipes to bring back inside through the bulkhead too. I think I'll stick with the idea of duplicating the standard setup in steel. I will probably bulkhead mount the clutch M/cyl too as it get in the way of the balance bar where its currently positioned on the die-cast ally frame. I think I'll fit a throttle pedal of a Subaru Impreza as the floor mounted one was a FBW version, I think a floor mounted throttle pedal will also make it more difficult to have a floor tray.

Martin

[squareright]

Martin,if I can move this along a long way,how do you propose to get around the CAS unit ( imoboliser ). The advantage is that you already have the stop start switch installed and with the added sequrity of this function it would be a shame to discard it.

Has the gearbox got the MSA system installed , would be a nice touch to incorporate this with a gear position display.

Sorry for moving it away from the subject at the moment but am just a little intreaged as to which way you are going on this.

If you are using a bespoke loom then obviously your choice , and I suppose this will be taken away from you.

Scott

[mef]

Hi Scott, Thanks for the interest.... I have completely stripped the car of its wiring, I will be re-wiring only the absolutely necessary basic functions, ie lights, wipers etc there will be no "body control ecu" or canbus stuff, it will all be hard wired in the old fasioned way! I want to keep it as simple as possible.

The engine will run on a DTA S80 ecu which will control the single vanos and I'll be making up the engine loom for that too. I have ditched the original engine loom as it's so heavy and cumbersome and there's so much in it that I wont be using at all.

I'm starting off with a standard M3 gearbox but hopefully will eventually get a Tractive sequential unit once I've sold my current rally car and can fund it!

We made some more progress last night, we stripped off the front and rear suspension. I cant believe how light the front hubs, struts, bottom arm, tension strut and ant roll bar are, they are really featherweight compared to anything else I've handled. The front discs and calipers are by far the heaviest parts. Conversely, the rear subframe complete with everything in one assembly is very heavy! I assume that BMW have done this to get their proclaimed 50/50 weight distribution?

Martin

[squareright]

Morning Martin thanks for the reply , you Are right in what you say refrence the weight issue. I have broken a knuckle in the past when I tried to catch a frt disc ( doh ). The suspension parts are designed to bend ,break etc to conserve body structure in a impact.

Scott

[Steve Moore]

Hi Martin
Finally registered so I could have a look at the new project, hows the cage coming along?

Steve

[mef]

Hi Steve, welcome to the forum!

No progress this weekend on the roll cage, we stripped all the suspension into individual parts and looked at the diff.

I need to take the diffs over to transmission specialist Hugo Kennedy (of ex RED fame) and see if its possible to re-build the E30 medium LSD assembly into a medium 1 series casing, it's not looking too promising due to various differences between them. One possibility is using a diff casing from an E36 3 series car but it will entail mods to the 1 series rear subframe diff mountings which is what I was initially trying to avoid.

I've now fully fitted both pairs of seat rails having finalised the seat positioning and worked out a solution to join the Corsa EPAS steering column to the BMW steering rack. All surplus brackets have now been removed from the interior.

I've no excuse now not to get on with the roll cage installation so I hope to press on this coming week.

Cheers,

Martin

[avtovaz]

Hi Martin
Finally registered so I could have a look at the new project, hows the cage coming along?

Steve

welcome to the forum


back to...