325i sport gearbox ratios

[Paynts]

can anyone tell me what the differnece in the reatios between a standard and a sport box is?
also can you get sport gearboxes second hand or are they like hens teeth?

[e301988325i]

325i..........1st 3.83, 2nd 2.20, 3rd 1.40, 4th 1.00, 5th 0.81, 3.64:1 open diff standard
325i sport 1st 3.35, 2nd 2.03, 3rd 1.36, 4th 1.00, 5th 0.81, 3.91:1 lsd standard (tech 2)

That makes interesting reading, I'd like a sport gearbox in mine thank you very much. something else to add to the list.

Does anyone know how to tell a sport gearbox, other than counting input/outputs?

[e301988325i]

I just made up a spread sheet, figures are based on a 7000rpm redline, 205/55 r15 tyres. I've not taken account of tyre deflection, slip or insufficient power.

325i, with 3.64

1st 3.83 35.4mph
2nd 2.20 61.6mph
3rd 1.40 96.8mph
4th 1.00 135.6mph
5th 0.81 167.4mph

325i sport with, 3.91:1 lsd standard (tech 2)

1st 3.35 37.7mph
2nd 2.03 62.2mph
3rd 1.36 92.8mph
4th 1.00 126.2mph
5th 0.81 155.8mph

sport box with 3.64

1st 3.35 40.5mph
2nd 2.03 66.8mph
3rd 1.36 99.7mph
4th 1.00 135.6mph
5th 0.81 167.4mph

320i g240 gearbox with 3.64

1st 3.72 36.4mph
2nd 2.02 67.1mph
3rd 1.32 102.7mph
4th 1.00 135.6mph
5th 0.81 167.4mph

[StuBeeDoo]

Does anyone know how to tell a sport gearbox, other than counting input/outputs?

The c/r 'box number (stamped in the bellhousing flange) starts with either "TNN" or "HM"

Interestingly, the 320i 'box has virtually identical ratios to the 325i c/r 'box. The exception is 1st, which is 3.72 in the 320i 'box.

[StuBeeDoo]

325i..........1st 3.83, 2nd 2.20, 3rd 1.40, 4th 1.00, 5th 0.81, 3.64:1 open diff standard
325i sport 1st 3.35, 2nd 2.03, 3rd 1.36, 4th 1.00, 5th 0.81, 3.91:1 lsd standard (tech 2)

320i.......... 1st 3.72, 2nd 2.02, 3rd 1.32, 4th 1.00, 5th 0.81.

[e301988325i]

Stuart, I've no idea c/r means other than compression ratio but that wouldn't make sense!!!

Lengthening 1st and 2nd by 5mph and 3rd by a little sounds useful to me, as I tend to change up to 2nd and then 3rd very quickly.

Sport gear box, new clutch and bearing, plus a lightened flywheel sounds like a nice improvement to me. My box is rumbly in neutral with the clutch engaged and changing from 1st to 2nd takes ages (worn synchros I'm guessing).

[StuBeeDoo]

Stuart, I've no idea c/r means other than compression ratio but that wouldn't make sense!!!

Close ratio!

[e30cbe]

http://www.unixnerd.demon.co.uk/revs.html

ratios/rpm/speed calculator

[bpowell555]

The 325i Touring has the 3.91 open diff as standard, does it also have the standard gearbox?

[StuBeeDoo]

The 325i Touring has the 3.91 open diff as standard, does it also have the standard gearbox?

AFAIK, yes. But IIRC you could specify a close ratio 'box in any 325i from new.

[bpowell555]

The 325i Touring has the 3.91 open diff as standard, does it also have the standard gearbox?

AFAIK, yes. But IIRC you could specify a close ratio 'box in any 325i from new.

I'm trying to think how I could work this out but I'm out of brain juice

[e301988325i]

What do you want to work out?? I'll do it

[Dave_M3]

A 318iS gearbox is pretty much the same as the Sport close ratio box too... which is probably why a good iS has some sort of a chance against a normal tired 325i.

Tourings with close ratio boxes are pretty hard to come by... would have probably been the last thing to be ticked on the options list when somebody pondering buying a silly speced touring 20 years ago which could end up nearly 40 grand when all done.

[StuBeeDoo]

A 318iS gearbox is pretty much the same as the Sport close ratio box too...

.... Because it has the same ratios as the 320i.

[Paynts]

ok where do i get one from ?!!! will a 320 box go go straight in? are 325 sport boxeshard to come by?

[StuBeeDoo]

ok where do i get one from ?!!! will a 320 box go go straight in? are 325 sport boxeshard to come by?

325i close ratio 'boxes aren't the easiest to find, and when they do appear, they usually command top money. You should find it easier to locate a 320i 'box, but you will also need the front prop to go with it as the 'box is shorter than the 325i one.
HTH
Stuart.

[e30topless]

ok where do i get one from ?!!! will a 320 box go go straight in? are 325 sport boxeshard to come by?

325i close ratio 'boxes aren't the easiest to find, and when they do appear, they usually command top money. You should find it easier to locate a 320i 'box, but you will also need the front prop to go with it as the 'box is shorter than the 325i one.
HTH
Stuart.

http://www.e30zone.net/modules.php?name ... 83#1641883

[Dave_M3]

I got a Sport box for a friend a few weeks ago for around a 150 euro....
Could have got a second one too if I really wanted it

[wess]

anyone know how to identify a 2.0 gearbox as am looking for one to put in my 325

[e301988325i]

It's not as strong as the 325 box and the prop-shaft will have to be lengthened as Stubeedoo mentioned above. Overall I don't beleive you'd make a saving, let alone in the long term.

[StuBeeDoo]

It's not as strong as the 325 box

There are at least 4 people here running 2.7s and 2.8s with the 320i 'box attached and no problems long-term.

[daimlerman]

I use a 320 'box with my 2.7 with no issues,even still using the lighter 320 clutch!
This is the Getrang 240 'box,same 'box is used in M40/42 but with a different casing to accomodate the differing engine angle.
When BMW developed the 325i,they went right through the car and upgraded any point that was thought to be lacking,bigger front struts,discs at the rear and so on.
The 360 Getrang as fitted to 325 has a bigger case to accomodate bigger bearings,it just confuses the issue that the 'sport' has slightly lower first three gears.

[Zaho49]

I want to know what is the part number of 325i Sport box and standart one?

[daimlerman]

Gearboxes have a code stamped into front edge of the bellhousing,according to Andy Everitt's 'Restoration Bible' sport 'boxes are HJ/TNN,standard 260 'box is NW,TNW,ANB.