Originally Posted by toobroketoretire

The myth of thermostats needing holes has got to be one of the silliest myths ever told. The "big three" manufacturers produced literally millions of engines using ordinary thermostats without holes and those engines are in use all over the world without any problems related to their thermostats. I have built over 1000 engines in my lifetime and never knew thermostats needed holes drilled into them until I joined a Corvette forum back in 2009.

Ignorant people start myths and it is ignorant people who perpetuate them

Originally Posted by toobroketoretire

The myth of thermostats needing holes has got to be one of the silliest myths ever told. The "big three" manufacturers produced literally millions of engines using ordinary thermostats without holes and those engines are in use all over the world without any problems related to their thermostats. I have built over 1000 engines in my lifetime and never knew thermostats needed holes drilled into them until I joined a Corvette forum back in 2009.

Ignorant people start myths and it is ignorant people who perpetuate them

Originally Posted by SH-60B

Silliest myth: "2B2R has an engineering degree."

Originally Posted by toobroketoretire

Of the 20-some myths I listed the "hot and running" myth is perhaps the silliest myth because one turn down is one turn down regardless of whether the engine is hot, cold, running, or not running. As the adjustment of hydraulic lifter plungers isn't the least bit critical anything between 3/4 turn to 1-1/2 turns down is plenty accurate. It takes a full 2-1/4 turns down to be able to hold a valve off it's seat so even 2 turns down would work just fine. As the valves slowly sink into their seats as the valves and seats wear the adjustment nut would have to be backed off to maintain "clearance" so 2 turns down would be too close for comfort. That's why G.M. chose an even 1 turn down as that positions the lifter plunger slightly less than dead center.

I don't know how on earth the myth of "1/2 turn down" adjustment ever got started but I suspect it came from the myth that 1/2 turn down prevents lifter pump up (which it doesn't) that happened with the old disc-type lifters used in the 1950's and early 1960's that did pump up very rapidly when the valves floated because of weak springs. Once the lifters got changed to the ball bearing check valve style and spring technology improved lifter pump up problems vanished.

The only way lifter pump up could be prevented was by giving the valves .001 to .003" lash and then you had the equivalent of running solid lifters on a hydraulic lifter camshaft but with bad valve train geometry.