Morris Minor Owners Club

hi folks, dad is toying with the idea of playing with one of the 1098's we have down the side of the house. I currently have a 270 duration cam, designed for a 1275 that is just kicking around. i was curious if it is possible to put this in the 1098? i know the lift would be pretty extreme for the little engine but would eliminate the need to buy another one! currently looking at rebore, 940 head, 1.75 carb, mated to a 5 speed.
let me know what you think! BMCecosse...i look forward to the reply!

Why would it have extreme lift ? It may have - but not necessarily so. Will depend on who ground the cam. If used with a 940 head - you would need to worry about valves hitting the block (if indeed it is extreme lift) - so 'pockets' would be required in the block (see pic). If normal lift - probably get away with just 'sinking' the exhaust valves by 40 thou - but DO measure it up carefully!
270 duration (approximates to BMC 731 cam which is 268 duration - but has no more lift than the standard 1098 cam) would mean the power will all be at highish revs - and of course the 1098 is the longest stroke engine - and not a great revver! The 731 is not considered to be a 'good' cam !
Oil pump would also need to be matched to the cam drive - and best to fit new followers if changing the cam. I would say - MG Metro cam is about as much as you would really want in a 1098. It has 252 duration on inlets and 268 on exhaust. Same lift as standard - it works v well. But - you have the 270 cam in stock - so why not give it a go!! But to get the best from it - the engine should be improved with larger valves and larger carb - it will be hopeless on an otherwise standard engine.<br><br>

BMC, sorry for the delay in replying, i only just saw the response! i wasn't intentionally being rude!
thanks for the explanation regarding the cam, makes it a lot simpler to understand! i will let dad know all this. he has a Metro big valve 940 head, i didn't think it would be possible to fit this, i thought it was jsu teth standard smaller valve 940 head that is fitted. we have both so either can be used, if possible the bigger valve one would be cool. he's got a toyota 5 speed that he wants to fit to it, and already has a 1.75 carb and LCB(he's running a 1275 at the moment, but needs a rebuild) so most "other" bits are already there. it's just the machining that will cost the most me thinks. i'm trying to convince him to buy bigger pistons, not really sure why, just like him spending money rather than me!

The 'big valve' head CAN be fitted - but really - the normal 940 head (with some work on the exhaust throats/ports at the bend) is enough for a 1098.

well that's okay, as i said, we have both so either can be fitted. by the sound of it, smaller is easier. easier is good! why does it need work on the exhaust throats? is that just to maximise power?

If you stick a finger down the exhaust throat (!) - you will find it is VERY restrictive where the port bends round past the exhaust valve guide boss. If you open this up with a few minutes grindstone work - it makes it SO much easier for the exaust gases to escape! Even if you do nothing else to the head - this is VERY worthwhile.