Sorry earlier comment had the word 'timing' missing.

Quick test for the valve once the head is off, put it upside down turn cams until all valves are closed on each cylinder (one at a time) and fill the chamber with petrol and see how long it takes to empty, if it's very quick you have damaged valves or they need a re lap

yes all plugs removed and fuel depressurised

it has white smoke from exhaust and missis every now and again.

Did you do it with all the spark plugs removed??

Why are you doing a compression test anyway?? Does it have a problem.

in middle of taking head of know , ball ache got rocker cover and top inlet off so far

about 5 seconds each cylinder

cranked until it would not move any higher

Has the changed? Check it all lines up with all the marks again, as it may have clipped the valves

Seems very low how long did you crank each cyclinder over for? For a 64k I'd expect higher unless head has valve damage, rings wouldn't wear out that fast and highly unlikely head gasket would go on all cyclinders at the same time

engines only done 64k

ok test results
(dry) cylinder 1 50psi
cylinder 2 50psi
cylinder 3 50psi
cylinder 4 50psi

(wet) cylinder 1 60psi
cylinder 2 60psi
cylinder 3 75psi
cylinder 4 75psi

it was only a cheap testing kit but what are your thoughts...rings(bore), valves/ stems seals, or head gasket..

Ideally 140 and above, ultimately want them as close to each other across all 4 cyclinders. Do a dry test and then a wet test (poor cap full of oil in each cyclinder as you go and then test) and compare both dry and wet readings

Just had a look and lists no actual values, just states how to do the procedure and what certain drops in compression mean.

cheers mate

As long as they are roughly the same I wouldn't worry to much, I have a Haynes manual, i'll have a look later on

doing a compression test tomorrow on my corsa b 1.4 sport (x14xe). anyone know what the compression readings on a healthy engine should be. have looked and cant find the information any ware.