Freeway use final drives - All sold

[Sean1380]

Hi guys

I have a mate in the UK who is having a major clean up, and has some crown wheel and pinions that may be of interest to us in SA.

As you are aware, our local Minis tend to run out of revs on the freeway, the 3.44 final drive in our local 1275 means you are doing around 4,600 rpm at 120kph (not sure of exact number, but am sure Boyscout or Miniac will know). and our little short stroke 1100s generally have a 3.76 diff  which means probably close to 5,000 rpm at 120.

So my mate is stripping 3.1s, 3.2s and 2.9 CWP out of gearboxes.

Now to put this into perspective, a 3.2 will drop your revs in top by about 320 rpm, and a 3.1 will drop it by over 400rpm.

The longer 2.9 is really only suited to Minis with good powerful torquey engines, and not those running hairy arsed cams such as a 286 or a 296, as it will make traffic a bit of a pain in the behind :-) as it will drop your 4th gear revs at 120 by over 700 rpm.

So with this all in mind, there will be limited stock, so i just want names and diff sizes at the moment.

Prices still to be confirmed though.

Thanks

[u09521]

Without reading up - can you swop it out without removing the whole engine?
I keep looking for another gear - probably a 3.2 would do?

[Junaid]

I'm interested in a 3.1, (price will determine if I can buy it)

[Jared Mk3]

Price dependent, I might be interested.

[Miniac]

Unfortunately the motor needs to come out as you'll need to remove both crown wheel and pinion to do the conversion and there are lock tabs that need to be knocked flat in order to undo the bolts holding them in.

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Both of these are based on the common use of 13" Rims fitted with 175/50/13 tyres...

(*)3.444 diff ratio cruising at 120km/h will be revving at +/-4350rpm

(*)3.765 diff ratio cruising at 120km/h will be revving at +/-4750rpm

The following are the 2.9, 3.1 and 3.2 equivalents there after followed by the above for ease of comparison... 

2.950= +/-3695rpm

3.105= +/-3880rpm

3.211= +/-4035rpm

3.444= +/-4350rpm(*)

3.765= +/-4750rpm(*)

[Sean1380]

Good info, thanks Ed

[Miniac]

Not a problem at all

[DomMINIque]

Sean I'd be keen for a 3.1 price dependent

[Sean1380]

As soon as i get confirmation from my mate RE prices and the qty available, i will let you all know.

[Boyscout]

Here is my version, 
   
I have also included a column to give you the rolling radius so you can check if you may have potential clearance issues.

If you guys send me a pm with your email I can share the XLS file so you can do your own calcs.