When I bought my Panda I had with it a 1242 bottom end and told by the previous owner that he could not fit a 999cc head to it.

I came accross another 999cc head yesterday (one with fuel pump) and having placed it on the block cant see any problems with it actually bolting on, so what I wonder would be the actual thing stopping it fitting on?

I have looked at the manual and found that there is a difference of 0.9mm in the cam lift from the 1108cc and the 999cc and I understand that the 1108cc and 1242cc head is the same. I would think that the cam might be a problem, though through looking at the guides you can put an earlier cam on a punto engine to run a mechanical pump.

I thought that the 1108 for the Panda was injected, though could be wrong.


Many thanks,

Jon

Even if it bolts on, all the oil passages match and all the rest is good, I think this could be a VERY bad idea. Measure straight across one of the cylinders and do the same with a combustion chamber in the head. Do you get the same number each time? I suspect the 999 engine has a smaller bore and will have smaller combustion chambers. That means your compression ratio will go up, and maybe by too much. At best, this will require premium petrol. At worst, the internal pressures will do their best to escape by any means they can, such as around the valves, rings, or even blow your head gasket in extreme cases. Another possibility is that the 999's valves will hit the piston tops during operation, especially if the pistons have notches for valve clearence. The 999 valves most likely will not line up with the 1242 notches if the bores are different or the inclination of the valves is different between the two.

There's more...If both engines are overhead cam, make sure the drive pulley on the 1242 engine is the same diameter is the same as the one on the 999. If not, you'll throw the valve timing off and end up wishing you had stayed in bed that morning! If both cams are in the block, make sure the push rods line up properly with the rocker arms.

OK, I'm just talking general principles here and I hope someone who knows the specs of the engines concerned will come on here and give you detailed information. My gut feeling on this is DON'T DO IT.

It will fit and is no problem.