1.2 and 1.3 valves the same ?

[jimbob-mcgrew]

any difference, or exactly the same ?

also, has anyone got any measurements please, ta

[Royston]

pretty sure they are the same (cathedral ports)

[jimbob-mcgrew]

took a while, but i found out there 33mm and 29mm.

and some engines had 0.075 to 0.25 mm oversize too.

45 degree seat angle.

[craig green]

This sort of information is in the Haynes bible, more likely in the older blue issue than the later (less info) green issue.

[millworm]

If it helps the 12st was the bigger valve engine

[jimbob-mcgrew]

This sort of information is in the Haynes bible, more likely in the older blue issue than the later (less info) green issue.

i couldnt find any info on valve diameters in all 3 of my haynes manuals. i do have the pooie green one tho. the other 2 are probably pooie versions of other vauxhalls too. :(


If it helps the 12st was the bigger valve engine

i couldnt find any info on differences between them, but on vauxhall car parts site, there under different part numbers, so must have some differences.

i did come across some intriguing pictures of head chambers tho.
i think the 12st chamber is alot smaller than the 12nv, altho i cant find enough pictures of either to confirm, and not sure if im getting mixed up with the early cast iron heads vs. aluminium. confused dot org

[millworm]

My auto grass mate says 12st heads are the better ones because of the bigger valves, that's all I know