also , gaskets "squish out"and thus crack&leek. you can add a aluminum washer about 2/3 the thickness of the gasket so when tightened it seats on the washer, not squishing the gasket to death..premature death from the pressure. most modern ruber & sily cone gaskets have these either molden in the gaskets or nubs on the part that seat at the proper preload...and as far as preload that is somethen you can determine to see what the washer thickness to gsasket ratio needs to be. just leave a gap somewhere where you can masure the amount of gasket squish when torqued . proper tq is for the fastner most of the time, not the gaskets.but your gasket is softer than the paper and will probably compress more. but thats ok as long as your not damaging the gasket.I suppose you could make a jig with big bolts and squeze the **** out of a gasket checking the compression as well as when the gasket is damaged.then you know how much is to much tq. but a press with pressure gauge would be best, but I dont think thats necessary. I would just knotch a gasket&check the amout of compression when torqued and that would probably be the optimum thickness or close to it. most all style gaskets loosen up the fastners after a few heat cycles.with the washers(preload spacers) that is nolonger a issue. to add to that most gaskets can be retorqued 1 time, then they will loosen again some if you keep retightening them thats when the crack& fail prematurly. as you have squished the **** out of them.not a failure in the gasket, but a failure in the tinkeritis persons knolage. good luck and keep comming up with great stuff!!!( I wish you lived next to me, we could come up with all kinds of stuff.