So now he's got his nice wheels it's time to give the little old chap a bit of pep

I had all the old Mini stuff laying around so I though it might be better put to good use

A nice 12G940 un-leaded head with nice big vales would be a start but the valve and bore spacing on the 1275 head is different to the 1098 and valves hitting the top of the block is an issue[xx(] There are a couple of ways around this the first being to 'pocket' the block where a recess is formed to give the valve room, another way is to cut the valve seat so the valve sits lower in the head. The magic number is .320" between (closed) valve face and the head face. As the clearance problem is only with the exhaust valves, and there's loads of meat on them, I decided to trim the valve face back to give the desired clearance.
Still plenty of meat left even after skimming
Now clearance ranges between .322" and .325"[^]
I decided to use a HS4 1 1/2" SU (sorry Tim:I), as any bigger on a standard 1098 just seems too much, and fit it to the manifold I nicked off a Mini 1100 engine I just happened to have kicking about. A couple of advantages in that it holds the carb at the correct angle and the existing exhaust fits straight on. Eventually I'll need a new exhaust and I'll fit a larger bore one but need to find a matching manifold to go with the alloy inlet manifold I already have[^]
While I was at it I fitted a crank shaft damper pulley.
New head ready to fit
Old head
I had to use the 1098 rocker assembly but this needed attering to suit the 1275 valve spacing
You can see in this pic how the rockers don't line up with the valve stems
Some rockers needed packing away from the support pillars with washers while others needed filing down to position them. The end ones just needed the tension springs fitting on the opposite side of the rocker.
I opened up the exhaust manifold to match the ports on the head
As he was
The new installation
But then I decided it needed some bling[8D]
And so after initial set up I took him for a blast up the road - a bit disappointing [V] But after a few tweaks on the mixture screw I got him running a lot better and much nippier - but I think I need an AAA needle as the one fitted seems a bit lean. The only problem is the noise from the K&N, for my daily driver it just doesn't seem appropriate so I think I'll try it with the original Mini filter (sorry again Tim) but it's got to be better than the tiny thing that was on there originally