Agreed. I guess it depends on how much math/chem/engineering you've been exposed to.I can't stop reading this subject. Very interesting but pretty difficult to understand.
So quick math:
According to UB excel sheet, Motorcraft 5w-50 shears about 30% (average)
Then if MC 5w-50 has a HTHS @ 3.7 (still didn't find the number)
3.7 - 15% = 3.145
That's the same I found when looking into where UB was getting his 'estimated' HTHS numbers. The problem is taking an average, then applying 'about half' of a percentage from an unknown baseline, then using a number that might be a minimum spec value and doesn't even have the same dimensional units.
Grant, it seems UB number were correct. IF the guy from BITOG is correct which I believe is.
By the way do you know Ford HTHS recommendation for the coyote/roadrunner engine?
I don't know how low you can go to keep the engine safe in a road race. A
And too high is not a good option either.
Believing it to be correct is one thing. Knowing if it's accurate is another. The problems are in the assumptions and error ranges. Testing actual samples would be the only way to know.
I haven't found a recommended HT/HS spec. The only official recommendations I know of are the change intervals based on track time listed in the Boss supplemental manual. I'm sure it's conservative, but why do differently when this should have come from the on-track data and durability tests from the 302Rs during the 2010 racing season and the Coyote development testing?