Diff identification

[webbnuts]

Hi all. hope you've all been out in the sunshine today in the Minors!

Quick question, I have the standard diff in my Traveller, but am building a new engine for it which will hopefully have a bit more grunt, and as a result I'd like to change the diff to the one that gives lower revs at higher speeds. I can't remember the ratios without looking them up, but is there an easy way to identify the different diffs, or do I need to get my hands dirty and count the teeth?

Thanks in advance,

Webbnuts

[mike.perry]

I am informed that the diff ratio is stamped on the diff housing. If you feel like removing the the diff from the axle then it is stamped on the crown wheel.
The commonly available diff ratios are listed on the Series MM website http://seriesmm.mmoc.org.uk ,car ident.

[bmcecosse]

If your engine is a 948 then go for a 4.22 (ex 1098 car) or a 3.9 (ex Spridget) If 1098 then go for that 3.9 or (better) a 3.7 ex late Spridget or any W 1500 or R 1.5. If using a 3.7 then a 1248 speedo from a Mini gives perfect speed and miles.