head height troubles

[gordini83]

Guys I'm about to assemble the block and head but when I measure the height of the head it's 79.5mm, according to an old email from Salv Sacco it should be 79.8mm. Usually this wouldn't bother me but the head gasket I removed was already large (1.9mm) and there were valve marks on 3 of the pistons (the final piston had a bent conrod!!). Can someone

a) measure a 'good' head height or

b) provide details of where a reconditioned head can be obtained.

My cylinder head of 79.5mm has been skimmed already by me, and possibly again before that. Reading on here skimming is a bad idea for some reason (must be for hieght??) Skimming gives you a nice flat surface.

Thanks

Pete

 

[miguelassis]

Hi,

I have an old workshop manual and it reads the following:

R1223 840-25 engine, 10:1 compression, 79,30 head height, 43cc chambers
R122B 840-26 or C6J-7-28 engine, 8,6:1 compression, 79,80 head height, 45,3cc chambers
R122B C6J-7-50 engine, 8,6:1 compression, 79,30 (!?) head height, 43cc chambers (first model)
R122B C6J-7-50 engine, 8,6:1 compression, 79,80 head height, 45,3cc chambers (second model)

The difference between the last two must be the pistons. Smaller chambers but same compression ratio. Or maybe a shorter conrod.

Hope it helps,
Regards,
Miguel Assis

83 Alpine Turbo with 220.000 KM still with original engine and turbo!