Morris Minor Owners Club

This is all theoretical so don't jump on me telling me what else would be cheaper or better!

Seeing as the 1098 has the longest stroke of all the A series engines, would it be possible to fit a 1098 crank to a 1275 to up the displacement (and hopefully power)

I was thinking either the pistons would need machining to not stick out of the block, or they'd need to be specially made if too much material needs to go. Assuming the pistons can be sorted are there any other potential issues?

It is indeed possible - using the later 'big mains' crank from a 10CC engine. And yes - it would push the pistons out the top of the 1275 block (which is already ~ 3/8" taller than a 1098 block) - so the pistons will need to be machined down - or specially made - or I suppose you could have a special short set of con rods made - probably not inexpensive. With maximum overbore you can probably get to almost 1500cc. BUT - the cylinder head is not able to flow sufficient air to make any more power - so unless you plan to force charge the engine - it's a futile exercise !

I see, I thought as much.

So the head and airflow is the limiting factor... seeing as I'm already into the realms of expensive and pointless...

BMW Bike head and a blower?


If I had two coins to rub together I'd be dangerous

Beemer head will help. But frankly - there comes a point where it's all just not worth it - a new Zetec can be yours for not much money and is a much more sensible way forward!