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3.7. what a DIFF (erence!)

Posted: Sat Aug 20, 2011 9:50 pm
by horrace
just fitted a 3.7 diff (instead of the 4.55 standard in the pick up) and by jiminy it has made a massive difference. i have 1.5 su carb, lcb and larger exhaust and it all seems to work very well so far, i was going to upgrade to a 1275 head but unless it proves economy (????????) i wont bother. just thought the info might be useful for other people thinking of upgrading.

Re: 3.7. what a DIFF (erence!)

Posted: Sat Aug 20, 2011 10:13 pm
by mike.perry
Have you changed the speedo?

Re: 3.7. what a DIFF (erence!)

Posted: Sat Aug 20, 2011 10:26 pm
by horrace
no, beffffore it was about 20% out and now it is spot on up to 50 mph and about 2mph out at 60mph, so im pretty sure it was the wrong one initially, this was another reason for changing the diff!

Re: 3.7. what a DIFF (erence!)

Posted: Sun Aug 21, 2011 9:13 am
by bmcecosse
Good plan then! The lighter pick-up will handle that final drive better than my heavy Trav. The 940 head makes a big difference to performance - but the temptation then is of course to use the performance - and away goes the economy........

Re: 3.7. what a DIFF (erence!)

Posted: Wed Aug 31, 2011 2:12 am
by Bazzalucas
Just received my 3.7 diff (from a '79 Midget). Will report back as soon as I have put it in. (1958 Moggie with 1275 and Midget trans, 3.9 diff).

Re: 3.7. what a DIFF (erence!)

Posted: Wed Aug 31, 2011 9:45 am
by dunketh
I always wanted one of these but they were doing silly money. Still, cheaper than a 5 speed conversion (but what isnt? :lol: ).
Were they only used in Midgets? What did the Wolseley/Riley cars use?