M type/ Minor differentials

This thread is for discussing technical topics.

Moderators: Ian Grace, Will Grace

Post Reply
sv4670
Posts: 72
Joined: Wed Jan 18, 2012 12:15 pm

M type/ Minor differentials

Post by sv4670 »

Can someone tell me are Minor and M type differential assemblies interchangeable and what are the final drive ratios?
I am wondering about fitting a lower ratio as the car will be used for trials. I see four star diffs are availabe for MMM MGs, will they fit a M type?
All advice gratefully received
Ian Grace
Site Admin
Posts: 5035
Joined: Sun Nov 19, 2006 12:55 am
Location: USA

Re: M type/ Minor differentials

Post by Ian Grace »

Happy New Year Derek.

For trials, I'd go for a 7/37 - lower ratio and stronger pinion because it had fatter teeth. But remember Ronald Trumpi over in Holland is searching for one of these too. :o

Ian
sv4670
Posts: 72
Joined: Wed Jan 18, 2012 12:15 pm

Re: M type/ Minor differentials

Post by sv4670 »

Thanks Ian and happy New Year to you too!

The chap I bought my car from has stacks of Minr bits rusting in the back of his barn. I might be able to get a diff from him. Is it possible to tell the ratio without taking the assembly out of the axle casing - is the ratio stamped on the casting or something?

It occured to me that the diff from a modern vehicle might fit - a little Suzuki pick up truck or similar. My justification for this is to preserve the original M type diff. I understand MG Y type diffs can be made to fit without much of problem and they have a four star diff. Probably not so easy to find though.
garagiste
Posts: 93
Joined: Wed Jun 15, 2011 8:22 pm

Re: M type/ Minor differentials

Post by garagiste »

From memory the numbers are stamped on the top of the aluminium nose.

However BEWARE all the carriers are similar and the innards could differ from the ratio shown on the housing.

Is it not possible to check the ratio by counting the number of turns of the input and those of the half shaft?
peterb
Posts: 73
Joined: Mon Mar 24, 2008 9:30 am

Re: M type/ Minor differentials

Post by peterb »

!934 saloon diff. Number stamped on aluminium casting: 8/43
I believe other ratios used were 6/33 and 7/37
Attachments
diff.jpg
diff.jpg (72.14 KiB) Viewed 6569 times
Sam Christie
Posts: 186
Joined: Mon Nov 20, 2006 10:37 am

Re: M type/ Minor differentials

Post by Sam Christie »

I wonder what the 'S' signifies in the case.

Image
Simon
Posts: 275
Joined: Sat Dec 09, 2006 4:56 pm
Location: Surrey UK

Re: M type/ Minor differentials

Post by Simon »

Does anyone know which vehicle the 6 / 33 ratio was used on.
Ian Grace
Site Admin
Posts: 5035
Joined: Sun Nov 19, 2006 12:55 am
Location: USA

Re: M type/ Minor differentials

Post by Ian Grace »

Sam,

No idea what the S stands for, but doesn't the dip stick make this a Morris 8 (or similar) diff.?

Can't be categorical, but not sure any Minors/M Types had diff. dipsticks.
Sam Christie
Posts: 186
Joined: Mon Nov 20, 2006 10:37 am

Re: M type/ Minor differentials

Post by Sam Christie »

Indeed I believe it is a Morris 8 diff. I understand it will fit a Minor/M-type axle which is why I have it in reserve.
Ian Grace
Site Admin
Posts: 5035
Joined: Sun Nov 19, 2006 12:55 am
Location: USA

Re: M type/ Minor differentials

Post by Ian Grace »

As my old drill Sergeant used to say, while brandishing his pace stick somewhat menacingly, "It WILL fit"!
sv4670
Posts: 72
Joined: Wed Jan 18, 2012 12:15 pm

Re: M type/ Minor differentials

Post by sv4670 »

Thanks for the advice, I wonder what other diffs will fit. I have a modern Morris Minor diff somehwere in the garage. I may see if that can be made to fit this weekend if I have a minute - need to get the other car ready for the Measham rally though. :)
sv4670
Posts: 72
Joined: Wed Jan 18, 2012 12:15 pm

Re: M type/ Minor differentials

Post by sv4670 »

Just acquired a 9/44 ratio diff. The casing is stamped with a large letter M. Did M type diffs have this rather than the ratio stamped on?
Attachments
diff 001.JPG
diff 001.JPG (2.53 MiB) Viewed 6497 times
Post Reply