engine and drivetrain Contribution to Article: Choice of transmissions

[Guest Anonymous]

URL: http://www.pbase.com/image/717418

Michel says:

I'd add that my choice would be the close ratio 5 speed from a 2002. I have 2 of those (not for sale)

unquote...

but my choice is the 262 close ratio 5 speed from an M5. Much stronger, newer, and bolts right up to a M10 or S14 block. If you use a 2002A body, the job of widening the tunnel is less, but we used a 2002 manual body, cut out the transmission mounts, spread the tunnel and added a new crossmember. With modern tyres (I use 225*50*15 Yokohama wet weather race rubber on 7*15 rims), transmissions can encounter much higher loads, so the M5/M3 262 is a good, genuine BMW, modern upgrade for a 2002.

Few people seem to know that the 262 fits a 2002, so you can find them for sale (be quick). They are not only much stronger than the 2002 CR, they are not so rare and not so expensive!

The downside is they have an odd shift pattern. First is a dogleg (left and back) with the upper four ratios in a conventional H. The 1-2 shift has to be deliberate, but, once rolling, you just use 2-5. Fifth is direct 1:1, like 4th on the standard 2002 box, so choose your diff ratio to suit (say 12% taller than you would use with a 320i five speed overdrive box)

Glen

'74 tii Alpina "West"

'81 733i DD

'69 Peugeot 404i

'78 International D1510 transporter

In #159, Don C good-naturedly queried my use of "bolts right up" in describing the installation of a 262 CR box to a M10 2002.

G'day, Don. I take your point, mate. My "bolts right up" was meant literally. The 262 bell housing bolts directly to the M10 engine casting. There is no need for an adaptor plate as with many gearbox (such as Toyota Supra into anything else) conversions. But you are right to raise other questions about such a conversion, as did many direct emails which I will answer with this post.

I figure anyone slightly interested in putting a strong close ratio gearbox in a 2002 is not even slightly interested in keeping a stock standard, concours car. My car is road registered, and I have taken it shopping, just to prove a point. But it is a very dedicated, very highly developed competition car. The wheels and tyre ("tire") specs I gave are a tipoff. My diff is a Borg Warner from a V8 Supercar, rated for 600bhp. So you will understand that I consider adapting a speedo drive cable and a drive shaft to be relatively minor details.

Yes, my speedo cable has 262 fittings one end and 2002 fittings the other end. Not that it matters for anything other than legal compliance, because the speedo display is hidden from direct view by a 10,000 RPM electronic tacho the size of a dinner plate, mounted on a bracket above the (lowered and extended) steering column. There is a TerraTrip 202 ("Terror Trip") on the dash which gives two displays, one of which is digital speed whenever that is required (it drives off sensors on front wheel).

Yes, I have a custom drive shaft of non-stock length. It is one-piece, large diameter lightweight tubing and was balanced to 0.3 gram specs on a truck crankshaft balancer.

So my post was intended for anyone considering an 'ideal' gearbox for a competition 2002. I love people who love stock, concours cars (and I have such a car myself) but most "stock standard" people have very different ideas from "highly modified" people... but I digress...

I am told, off-post, that 262 CR boxes are rare in US. Well, they are not exactly plentiful anywhere. Mine came from Europe. But old M5/M3 cars sometimes get wasted and gearboxes tend to survive most (sedan) crashes, so they are available. Whereas a genuine 2002CR box is terribly difficult to buy.

Someone pointed out off-post that the 262 CR is heavier than a 2002 CR original. Quite so. And rated for much higher load, too! At least it is the best possible place to add weight to your car. I have a carbon fibre bonnet ("hood") with no hinges and a perspex back window and no fuel tank but a plastic fuel cell between the back struts, and a lightweight dry cell battery behind the passenger seat, all to get weight out of the ends of the car.

I hope that helps. At least, I hope that explains my perspective on "ideal" gearboxes for competition 2002s. I fully respect the positions of those who want a stock standard car, and choose a 4-speed, those who want the best performance from a "production" car and choose a 2002 5-speed CR, those who want easier high speed touring and choose a 320i 5-speed overdrive box, those who choose a Holinger, etc. My real objective is to make people aware of the 262 CR option, because it is often ignored in 2002 gearbox conversion discussions.

Cheers,

Glen

In all the words recently posted on 262CR 5 speed gearbox conversion, somebody said 'nuff words, let's see pictures'.

OK.

I documented the whole project on

http://communities.ninemsn.com.au/2002Alpina

but that has become partly corrupted by the system and the M'soft boffins have not sorted it out for several months. (Please send complaints to

web_communities_au@css.one.microsoft.com)

So I put some images on

http://www.pbase.com/glenbonnerdavis

Enjoy !

Glen

[Guest Anonymous]

thanks for the 262 CR tip