How would a standard xe run with standard cams and twin forties?

Very well. They are easy to set up the ignition side aswell i believe.

Ned??

would really want 45's, 40's would be a tad small, even on a bog std engine I'm afraid.

Setup wise though, no probs with std cams etc and carbs, all fine.

i will be running mine on 40,s
am being guided by a relly who ran
an xe powered corsa in club rallying
with a great deal of success

ppl have said to me you need 45's rather than 40's but IMO 40's will get plenty of air in there..