Slip in a new diff!

[Morrisminormo]

Since my 1098 upgrade for my 1957 (948cc) saloon, I feel I need to change my differential ratio. It flies up hills and pulls like a train ( you get my drift ) on its original 4:55 ratio but 50/55mph sounds like it's enough for the old girl! If I change to a later 1098 minor diff 4:22, is it just a case of drop the old and in with the new? This is my daily driver and I do 55 miles a day, so don't want to blow another engine!

I have a 948cc engine with big ends just started to knock if anyone's interested, with unleaded head less than a year old

[bmcecosse]

Yes - one out and one in. Won't make a huge difference though.......

[simmitc]

The 1098 diff will fit a 948 axle BUT you'll have a problem filling it with oil - the 948 diff has the filler plug on the front of the diff, whereas the 1098 axle casing has the filler plug on the rear of the casing. So, with a 1098 diff in a 948 case, you won;t have either hole

[Morrisminormo]

Yes - one out and one in. Won't make a huge difference though.......

I thought I may help me cruise at 60/65?

My old minors seemed to have more top end than this one

[minor65]

55/60 mph IS more than enough for the old girl. No matter if 948 or 1098.

[Morrisminormo]

If it was worth me doing, then a drill And a helicoil set is all I need.

[Morrisminormo]

55/60 mph IS more than enough for the old girl. No matter if 948 or 1098.

I agree that 60mph on 7 inch shoes is more than enough. I just wanted to drop the revs a little. I do have a rather loud exhaust on her that makes it sound more painfull than it really is.

Nice looking car you have there, very much like my own

[bmcecosse]

You can simply fill the oil in through the breather hole....

[minor65]

Ahhh right. Lower revs

Thanks, it's a 61. I only have it 6 weeks. I am the 2nd owner and it still has its original 948. My other 2 minors are 65, so 1098's. This will be the first 948 I will have driven and haven't yet as I'm still working on it.

[Morrisminormo]

Ahhh right. Lower revs

Thanks, it's a 61. I only have it 6 weeks. I am the 2nd owner and it still has its original 948. My other 2 minors are 65, so 1098's. This will be the first 948 I will have driven and haven't yet as I'm still working on it.

This was my first 948 too, the engine was super sweet, until the big ends went but I've upgraded to 1098 engine and box and the difference is remarkable.

I'm the 3rd owner from new, mine is 1957, I still use the trafficators what work you doing on yours??

[minor65]

Have a look in the restoration section and all will be revealed.