Thanks mate.
It's all interesting stuff although confusing too. All this stuff is a bit of a black art.
Oz Group C competition GTV6's used around 1200lbs of front spring (equivalent)plus big bars etc on slicks and handled pretty well.
My previous race car at around 200kg less than showroom weight used about half that rate and handled superbly on semi slicks.
The above spring is available from 175lbs to 1600lbs so I got a bit of room to move..
I am hoping the coupe will be similar in weight distribution and weight when I am finished so I will start with what worked before. I want to see the suspension doing some work and not just the tyres. Our tracks can be a bit bumpy in places that can unsettle cars that are too stiff.
As usual, the propshaft is getting a modification so here is the mod to the front donut. The PCDs are the same as the Alfa but the stud holes are 2mm bigger. This needs some packer spacers made to take up the slack.
I machined these spacers out of some solid bar and then trimmed them to length.
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Front donut conversion 1.jpg (90.4 KiB) Viewed 6611 times
Front donut conversion 2.jpg (87.71 KiB) Viewed 6612 times
Front donut conversion 3.jpg (80.22 KiB) Viewed 6610 times
are these the BMW donuts or XR6?
do you have a source where i can buy these?
from looking at the picture these dounts are thiner than the alfa ones, so would need a spacer to work with the standard propshaft. but i assume u are using a propshaft with universal joints?
Any place that supplies BMW parts. The number is 26 11 1229 065
Yes you have to pack out the fitment so it is the same thickness as the original. You can make specific washers or just use new ones.
Part number correction.
I accidentally pulled that off another invoice. That's one fitted behind the 3 litre in my GTV6.
The part number for the one in this photo is 26 117511 464
Sorry about that.This one is good for 192bhp. I am expecting around 170 so that should be ok.
Last edited by MD on Sun Oct 31, 2010 3:32 am, edited 1 time in total.
According to the bmw number it comes from a variety of beemers, but the 4.0 v8 models all seem to have them. Also the 3.0d versions off 3 and 5 series use these. so they should be able to handle a lot of torque...
they are 105mm pcd and with 14mm bolts. the old number was 26 11 1 227 690.
That exhaust indeed points me to a lot of torque... looks like there is a big snail on there feeding that huge exhaust.
You don't want to experience those things while driving. the remaining piece of axle might come right through the floor or smash itself into the road and launch you.
I have some beemer axles lying here and they are about the same thickness material as the ones Alfa uses...
wow that is serious torque to twist the shaft,
but surely with that much torque the wheels would have no traction and wouldnt be able to break the shaft like that?
BradGTV wrote:wow that is serious torque to twist the shaft,
but surely with that much torque the wheels would have no traction and wouldnt be able to break the shaft like that?
anyway it looks cool haha.
He must have had good grip that's for sure.. maybe dragracer-tyres?
MD wrote:Yes much stiffer (relatively) speaking. Lesser couplings are more compliant and you can twist them a little in your hand but not the V8 one.
I can imagine that being a problem as the engine in the Alfa normally moves to the side under load and that bmw donut wouldn't like that very much.
Putting the engine straight in the car ( not with the angle like original) on good engine mounts would probably help against that.
What i was wondering when i read about the v8 donut was if you couldn't use the entire BMW driveshaft ( cut to length offcourse). That way you would get only one rubber donut upfront and a U joint in the middle with a CV joint at the rear. On the front of the axle you could use the standard Alfa flange to fit the flywheel and on the rear an adapter would need to be made to fit against the gearbox.
That all sounds interesting but I already have a plan. I am using the above front donut with a one piece shaft and a UV at the rear. Hope to fit it during the week if I get a chance.
the remaining piece of axle might come right through the floor or smash itself into the road and launch you. 
