Sport Gearboxes!

Mon Jul 04, 2005 12:54 am

Couple of questions of sport gearboxes - firstly, what are the identifying numbers, and where are they located?

Secondly, what are the real advantages of a sport box over the standard box?

Q

Mon Jul 04, 2005 2:00 am

Getrag 260 its the strongest tranny ive ever driven on. its usuually found @ the right side of the tranny look @ it from the priciple end. 325i tranny that all u need.

Mon Jul 04, 2005 8:09 am

Think it's the bellhousing number on the right hand side.

If you wipe all the oily gunk off from under the output shaft, you'll find the gearbox number.

Can't remember what it's supposed to be for the sport box, did post it up a while ago though so a search should reveal it

Mon Jul 04, 2005 8:27 am

Ah Haa!

'ere we go: 260.0.1060.91 from under the output shaft

Mon Jul 04, 2005 9:44 am

Thanks M8

Mon Jul 04, 2005 11:32 am

Turbo-Brown wrote:Ah Haa!

'ere we go: 260.0.1060.91 from under the output shaft

yep i have 2 sport boxes and can confirm that

Mon Jul 04, 2005 1:15 pm

Well i think thats just the part number for the housing.

Im sure then only way to tell if its sport or not is by the gearbox number which is on a flat piece of the tip of the bell housing. And is unique to all gearboxes.

A

Mon Jul 04, 2005 1:33 pm

Anyhoo, advantages of a close ratio gearbox are that you can keep the engine closer to it's power band as each gear shift equates to less of an engine speed change.

Mon Jul 04, 2005 5:21 pm

it's only the ratios in 1st,2nd and 3rd that are different to a standard 325 box

Mon Jul 04, 2005 5:32 pm

Is it not meant to remove the gap between 2nd and 3rd or something?

Mon Jul 04, 2005 5:34 pm

I thought it was only 2nd + 3rd that where different Si??

Mon Jul 04, 2005 5:38 pm

no i'm right! 1st 2nd 3rd!!

Mon Jul 04, 2005 6:35 pm

325i...... 325i sports .......320i

1st-3.83...1st-3.35.......1st-3.72
2nd-2.20...2nd-2.03......2nd-2.02
3rd-1.40...3rd-1.36.......3rd-1.32
4th-1.00...4th-1.00.......4th-1.00
5th-0.81...5th-0.81.......5th-0.81

Mon Jul 04, 2005 10:06 pm

Guess it depends on the final drive ratio you use. My understanding is that the standard 325i has a 3.73:1 final drive ratio whereas the Sport has closer to 4:1 (3.93 or something?).

Anyhoo, I'm keeping the standard 325i final drive to give a Uber long first with the ratios nicely (I hope) stacked after that plus the benefit of quiet motorway cruising.

Mon Jul 04, 2005 10:13 pm

surely u'll want an lsd though and finding a 3.73 lsd is a tall order

easier to find a 3.64 or a 3.91

Fri Jul 08, 2005 2:08 pm

Or make a 3.73:1 LSD.

Am planning at some point to make a kind of constant lock (i.e. simple) LSD using the crown wheel from a 3.73 diff (when it turns up)

Reckon some EN3 steel should be 'ard enough.

Got a mate who owns a precision engineering firm and he says if I design it, he can make it

Mon Jul 11, 2005 11:06 am

I know who has a 3.7 lsd for sale and its good.

A

Mon Jul 11, 2005 2:03 pm

how much?

Q

Mon Jul 11, 2005 6:44 pm

now that would be telling but i saw it yesterday at brooklands 3.73 lsd!

think he wants Ãƒ”šÃ‚£350 for it