The numbers for computer simulation must have meaning or everything you do with them is WORTHLESS.

A rudimentary understanding of such things as laminar flow, Reynolds numbers and a bunch of other stuff is required or what you design is junk.

There are many "rules of thumb" I use that still work to this day...I suppose you could program those into simulation programs.


But herein lies the crux of the matter. Today's generation think the computer has revolutionized the world, that we are doing things now that have never been done and that is 100% arrogant horsecrap. Go find an early Oakland engine and look at what those engineers did WITHOUT CNC. And, evidently, we have forgotten/ignored or are ignorant of what was accomplished by THIS country WITHOUT computers during WWI and WWII.

All CNC means to me is that whatever you have that is CNC'd will be almost exactly alike, warts and all. The tool path is copied exactly the same, every time, even if there is no material there, or there is more metal there and you have tool deflection. All errors are copied as well.

As I see it, the public is getting screwed with CNC porting. By the time you fix the CNC work, you have the same money in the heads as you would if they were hand ported. And this is why the big companies tell you to leave them as is, they can't sell you a semi-finished head for retail.

There are exceptions to this rule, but the rule is correct none the less.