How cool is that 

Great picture Heo!  Now we need some more pictures of skinny Jay with long hair.  There are rumors that he has a great shot of a really nice looking girl sitting on the roll bar of his '68 GT-500 convertible...

You can't take the boy out of the boy!!  Uncle Heo is cool 

I remember years ago going with a friend on a shakedown in his '69 GT-500.  Dave's wife had him watching the three year old daughter, so we strapped the car seat into the back of the Shelby.

The car ran great!  After awhile Dave couldn't help himself and he mashed the throttle on a long straight.  As the smoke cleared, a little voice screamed out, "Do it again! Do it again!"

We spent the rest of the ride home trying to figure out how to do damage control with the wife.  Dave also resolved that he was going to buy his daughter a little four cylinder car when she turned 16.  No, her name is not Greta!

That car is absolutely beautiful!  Wow what a gem   

My untouched Ford cammer block was way off square when I had the shortblock rebuilt.  One deck was 0.026" off, so I believe what Brent is saying. 

I also worked in a Ford engine plant.  The maintenance on the big machines was minimal at best!  Often we had parallel machining lines and when one went down we would scrounge used spare parts from the other one to get running again.

Amazing what just a 1/16" of extra squeeze will do for you  Good info for people to use as research!!

What's probably happening is that he's getting closer to coil bind at full lift.  My work years ago on the SOHC valvetrain showed how this quiets down the surging motion of the spring coils at high rpm.  I found that setting up for around 0.050" from coil bind at full lift gives you the full benefit while staying safe.  The NASCAR guys run about 0.003" from coil bind 

They had some really cool machinery at Ford's EMDO (Engine Manufacturing Development Operations) Building, where most of that original stuff was made.  Gun drilling stuff like that was a breeze for those guys. 

When I was there they were experimenting with super high speed gun drilling of 5.0 block oil galleries.  The ceramic drills had 5,000 psi coolant coming out the tips, and they would run the length of the block in under three seconds    It was exciting when things went pear-shaped though.  The room walls and ceiling looked like someone had been tossing grenades in there.

I'm not sticking my head out on this one!! 

It seems that there isn't a bad answer here as long as you're methodical...

A high performance fastener, like a 12-point, will in general have more bearing area than a socket head cap screw.  The hardware store six-point Grade 8 you're comparing to isn't suitable for a critical application.

I don't care about showing people that I'm right.  All I care about is keeping people reading this forum from getting bad information.  In mechanical engineering practice, you will not see socket head cap screws used in critical, high performance joints.  They are inferior to the external Torx or 12-points that are in all of the specialty / racing / military / aerospace applications.  Those are what you want.