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Hi I was wondering if I can put a 1l head on a 1.3 block and if so what parts I have to change to 1.3 parts or 1l parts like head bolts, gasket etc thanks in advance

I seem to remember something about the HA head gasket having smaller bolt holes than the HC, but I’m not sure. If that is the case, then I think that the 1256 head bolts probably wouldn’t fit through the holes in the head. I’m sure someone more knowledgeable will be along soon to correct me.

Early 1056 blocks had 3/8 head bolts not sure if they changed later.1257 engines had 7/16 bolts it is possible to mix but it needs sleeves in the 1257 heads to reduce the holes for the head bolts to 3/8 as the bolts locate the head on the block

The above is correct in principle that there will be a bolt size difference, that will make the 1256 bolts impossible to get throw the smaller holes in the head.

even if you overcome that issue, with heli-coiliing the block to take a smaller bolt, you may find the oil gallery doesn't line up.

Some of the 1256 blocks have the main oil gallery slightly off line to the 1057 / 1159 heads, and other 1256 engine blocks have the oil gallery starring the same hole as an engine bolt. so beware.

I used to run a 1057 block with a ported and polished 1159 head which has 7/16th holes and yes the advice above to use a sleeve to locate the head square is correct, but you are doing this the other way around so it's not possible to fit a 1057 head to a 1256 for the two reasons above.