Quote:
That won't cause a head gasket problem. More likely to break a piston or bend a valve, but the A-series is tough.

Head gasket problems are almost always caused by these:
* Overheating
* wrong torque (fasten in three stages, circular pattern)
* incorrect prep. Block and head face impeccably clean, threads chased, not oiled

Less likely causes for a blown head gasket are:
* Defect in manufacture of gasket
* head warped past spec (4 thousands inch)
* Extrememly high combustion pressure (more than 10 pounds boost?)
* Bored in excess of 79 mm (may need fire rings)


Quote:
A ruler can measure to an accuracy of 1mm.

A15 with 79mm pistons: 1608cc
A15 with 80mm pistons: 1649cc