ORIGINAL: Four Stroker
I have an engineering book that says 3 times the diameter of the bolt !
Regular red is 350
High Temp is 450
Silicone is 450
The ''high temp'' will work only on nitro two strokes. On a four stroke nitro I melted alumiweld stuff that is 730 deg. I doubt any of the above will work on Gas either - but no experience.
I've been a first class fitter and machinist for 26 years and it has always been bolt diameter = thread depth as a minimum. Of course you can use more thread depth if you want and most tapped holes are deeper than 1 x diameter.
As for 3 times the diameter?? Buy a 1/2" bolt and nut for eg. and i guarantee the nut won't be 1 1/2" thick.
Anything will strip if it is over tightened too much. As i said, most modelers use too much force when tightening small bolts.