Morris Minor Owners Club

Am I correct in assuming that an OHV engine (1275 in particular) wont fit in my engine bay because of the bulkhead cross member getting in the way?

Not sure - I have seen splitty's with 1275's in but don't know how much work was needed to fit them - I can take some measurements if it would help off mine?

Thanks for the offer PSL, I would only ever consider the mod if it didn't involve any 'surgery' and I'm not sure what needs measuring!

I have seen a 1098 in a lowlight without the bulkhead being modified, however the 1275 has a larger head which can get in the way of dropping the back of the engine down to fit or remove the top gearbox bolts.
What engine do you have in at the moment?

Uuummm! Just a thought. I did recently sell my 1098 engine and 12g295 head that I was once going to fit but originality took over so it never happened!
My next question would have been has anyone mated a 1275 engine with the sidevalve gearbox - and if so for how long!

The bell housings are a completely different shape. So I would say no.
The MM box is pretty strong, after all it is quite capable of handling an Alta conversion and Keith Luck runs a supercharged Alta engine.

The bulkhead crossmember on the lowlights were flat or square for a want of a better description and needed some clearance putting in to fit an overhead valve engine. Sadly this was nearly always done with a large hammer!
The later Series MM's had the relief in place as they made the shells ready for the A-series so no clearance issues!
The other bit of surgery you WILL have to do is to the edge of the floorpan around the back of gearbox for clearance and change your handbrake to suit.
As Mike has said, the sidevalve gearbox is not suitable to re-use easily with the A-series engine.

As yours is a highlight MM, it may have the correct shaped crossmember in it. Try comparing it with a later Minor.

Your car being a late '52 will have the curved bulkhead crossmember so the engine bay will be the same as a M1000 and a 1275 will fit. But why spoil the character of an MM by fitting an A Series engine?

You are right! I dont want to spoil it, I think my brain cell must have had a 'spare moment'.
And you are right again! I have got the raised cross member.

Would the old MM diff cope with a 1275?

alanworland wrote:My next question would have been has anyone mated a 1275 engine with the sidevalve gearbox - and if so for how long!

There's a Series MM out here with a 1098cc engine & it's still using the original Series MM gearbox.
The gearbox is a lot stronger than the OHV units but they weigh a fair bit more.

alanworland wrote:Uuummm! Just a thought. I did recently sell my 1098 engine and 12g295 head that I was once going to fit but originality took over so it never happened!
My next question would have been has anyone mated a 1275 engine with the sidevalve gearbox - and if so for how long!

I was told the otherday about a low light with an a series in it (cant remember the size now) mounted to a sidevalve gearbox - using an alloy adaptor plate

apparently it went very well until about 60 at which point the revs took over

speaking of which
im currently rebuilding a 950 ( came with a bunch of parts i got and i just picked up a full gasket set for dirt cheap) may end up keeping it should i want to take the sidevalve out for work

Can't comment on the ulimate strenght of gearbox or back axle other than that they are both capable of handling a supercharged Alta conversion. Morris seem to build in more reserve into their components than Austin.