Morris Minor Owners Club

I have a Feb 1955 Series 2 Traveller that I am currently rebuilding. I will be installing a 1098 engine and I have just completed the underside metalwork. I want to upgrade the brakes and I currently plan to fit a disc conversion on the front and also a servo. My question relates to the rear brakes and whether these need uprating. Firstly, I see in the spares lists there are different brake parts for the early and late 803cc cars. As a 1955 car I am assuming mine counts as a “late 803cc” - am I correct in this assumption? If so I believe the rear brakes are as on later cars. Secondly, I see there is a different brake drum listed for the 1098 - what is the difference and if it can be fitted to earlier cars is there any benefit? And my last and third question is are there any simple upgrades suggested for the rear brakes - I would rather stick with a Morris Minor set up but just wondered if I have discs on the front should the rear brakes be upgraded as well? Any ideas or advice would be much appreciated.

The rears were 7" drums, which continued right through to end of Minor 1000 production. The actual parts differed over the years including cylinders but I'm not sure how much the differences were (e.g. I think one change was related to seal design).

Unless you are going for a track day car, the 7" rear drums are fine - it's possible to get 8" rears from other BMC applications, but the benefit is very small compared to front disks.

The reason it makes much less difference is that the better the front brakes get, the less effect the rear brakes can possibly have as the rear end grip reduces under braking. Added to that, more of the heat dissipation should go via the front brakes - heat capacity being the other reason for wanting to upgrade (but that is fixed by default if the front brakes are good).

The difference between the 1098 drums and earlier that you mention is with regard to the front ones- the 1098 cars all had 8" front drums, whereas MMs, SIIs and 948 '1000s' all had 7" front drums. The 8" front drums are noticeably more powerful than the 7" ones, but they are never going to be as resistant to fade as discs. They're fine for a standard 1098 car in my opinion though, and if they're kept in good order work surprisingly well.

Tony wrote: Firstly, I see in the spares lists there are different brake parts for the early and late 803cc cars. As a 1955 car I am assuming mine counts as a “late 803cc” - am I correct in this assumption? If so I believe the rear brakes are as on later cars.

The early 803 brakes will be the same as fitted to the sidevalve MM cars as the axle and hubs continued a little way into Series 2 production, offhand I think till late 53 (My June 53 car should have MM bits, but it now has later bigger brakes). these had integral hubs and brake drums and were differnent stud spacing to later cars, so different wheels.
Your '55 car will certainly be later Series 2 parts with 7" brakes allround. Easiest thing to do is to fit later 8"backplates and drums on the front as liammonty suggests unless you're going for a bigger engine in which case look on here for advice and views on discs v bigger drums...

As above really - for a simple engine upgrade, the later 8" front drums will be perfectly adequate - and NO servo required. Don't forget to change the final drive ratio to 4.22 (or even 3.9) when fitting that 1098 engine.

Thanks everyone for the advice. Your help is much appreciated. Tony

A further question comes to mind re the suggestion from bmcecosse re changing the diff. Thinking about it I will definitely need to make the final drive a bit more “long legged”. I do have a good spare 4.125 diff which came from an Austin Healey Sprite. Anyone know if this will fit a Morris 1000 please?

Not aware of a 4.125 ratio?? Are you sure ?? In general - any Spridget final drive will fit ok. You may not have a filler plug though! See here http://www.1978mgmidget.com/Special_Tun ... 8_1098.pdf
Scroll down to sheet B-7

Easiest way to do it is to fit a later minor 1000 axle. You can probably get one for a scrapper for the same price as a diff...
The filler changed between axle and diff between early and late minors. Various combinations can give you no filler or 2 fillers.

Thanks. Sorry I have not replied earlier but I was away in Derby yesterday. I see what you mean about fillers. There is none on the axle but one on the diff.

I am a little confused over the diff I have. It came out of a Mk1 Frogeye Sprite and according to spec in the BMC Workshop Manual it should be a 4.125. from your special tuning leaflet I think this might be a mistake! I have just counted teeth and I make it 9:38 which would make it 4.22. This diff has a filler so it should be OK with the axle I have. The reason it was removed from the Sprite (which I still have) is that I replaced it with a 3.9 to make the Sprite (which is now fitted with a 1275 engine) more long legged. I believe that 4.22 is the original ratio for a 1098 Minor Traveller so I appear to have a cheap solution. However, any advice as to whether this is a suitable ratio for modern driving in a Traveller with a standard 1098 engine would be very much appreciated.

that'd be perfect by the sounds of it!