oil on top of the head

Another thing not common thing not mentioned is that 15x4 = 60 total foots pounds on the head. So 20x4 =80, and 12x4 = 48 .
Metric Bolt Specs
A 3.5 horse power Briggs and Stratton is 165 inch pounds There are if I remember right 7 bolts to the head on one of those. Making a total of 96.25 foot pounds on the head.

It is a little rough to ask 4 bolts for the total torque of 7 like the briggs

The said Briggs has a piston about twice the size. Every time one re tightens a china's jug again. I would say the cylinder is getting more oval. Which would suggest more than 50 total foot pounds can be detrimental. So as I sound this out I would say officially no more than 12 to 13 foot pounds does sound about right. Sorry if I sounded miss leading. Still torquing a new engine new gaskets seating them all in 15 at new might not be be so terrible.

You guys have more guts than me. I look at those crappy threaded 6mm studs and nuts on my Grubee slant plug motor and I can't bring myself to put more than 10 ft lbs on my head studs. I have about 100 miles on it and have retorqued them three times and gotten movement on the nuts each time but no sign of leaks. I'm using Opti-2 oil at 100-1

Jim