Morris Minor Owners Club

I have the opportunity to buy an MG1100 engine complete with twin su's and "4 into 1" exhaust (I have yet to go and see this engine so I'm relying on the seller given information for now) The asking price is around 100 pounds which I figured could possily be a good way of upgrading either my 948 or a 1275. I have the 948 right now in my traveller but could always look for a marina sourced 1275 as either way I will be spending money on rebuilding the engine with unleaded head and some (mild) modifications on the way.

Could some of you maybe give me some input on whether buying the mg1100 engine would be a good move or a total waste of money? (I am aware that that exhaust manifold will need some some chopping around to fit in a minor as it comes off a fwd car though!)

The engine, whichever i use, will be backed by a sierra 5 speed and will only see (lively at times) road use - a long shot from my original plans for a zetec power...but for now a better choice as it is much more pocket friendly

If it really has a 4 in to 1 exhaust then it must have a special crossflow cylinder head fitted - an absolute bargain at £100 !
More likely - it has a very simple 3 in to 1 exhaust - and all you could use would be the 12G295 cylinder head and the twin carbs (not even the exhaust) from that engine. The head is good - but not the best, and a big single carb is better than these twins. So - if you could get the head and carbs for ~£50 that would be ok. The engine itself is no use for a Minor.

Hi Kustom, MG1100 is a transverse engine so is no good for a Minor as it has the same crank as a mini.If I were you I'd go for a 1275 which has a stronger bottom end.The manifold if meant for a transverse engine also will not fit.

The engine, whichever i use, will be backed by a sierra 5 speed

A 1275 will be a much better starting point if you are going to fit a 5-spd box. In which case the MG1100 engine has nothing useful to offer you, even though it does have a good head, but not for a 1275.

And - don't waste money worrying about 'unleaded head' - it's not necessary unless doing long hard miles - and some 1275 heads (all the later ones) are unleaded anyway! The Sierra 5 speed box modification is not inexpensive - I hope you have deep pockets! Poverty stricken folks like myself just source a 3.7 diff and fit that in the back axle. Only 4 gears, but 1st is still perfectly low and top gear running is much more relaxed - although a standard 948 would probably be struggling - as it would be in 5th gear on the S box !

First of all, thank you for all the information - you've practically saved me from paying for a lot of bits which I'd have had no use for otherwise!


Looks like 1275 will be the best way forward - I'll check about the carbs but might end up getting one big one up instead of the two. I have seen various references in threads on here claiming that with the exception of looking good, twin carbs seem to have no real benefit over a bigger one but I was still hoping the whole engine would have more useful bits to offer up!


BMCE Re the head...Maybe I can pick a recent one with unleaded-friendly valve seats cheapish then...Malta petrol is not exactly the highest quality and i'd rather play it safe as I want to drive my mog as often as I can As for the gearbox - was going to try and speak to a local engineering firm to see if they could hook up the morris and ford bellhousings together before looking into buying the readily available cast bellhousing as it is not the cheapest option available yes!

Don't worry about the 'unleaded' head - worst that happens is the valves recess slightly - just keep adjusting the valve gaps. The cylinder head from a later 998 Mini is unleaded - but has slightly smaller inlet valves (and poorer gas flow) - but would fit straight on but with a small power loss.