Ok, here's this newbie's thinking....

I ask myself, what makes the explosion occur?

Isn't it the fact that the fuel/air mixture has been heated/compressed? And if that is true, wouldn't the fuel/air mixture have to be in the cylinder before the compression reaches maximum? And therefore, doesn't that imply that the injection timing has to be BTDC, which is the point of maximum compression?

After all, after TDC, isn't the compression lessening?

Or am I oversimplifying?

__________________
MB 1986 190D in my past
MB 1987 300E on the street
MB 1994 'Smoke Silver' E420 in my driveway
1999 Mazda Miata in the fun stable
1964 E-Type Jaguar Coupe- Sold
1970 E-Type Jaguar Coupe- Sold
1968 Corvair Monza Conv. with Turbo Transplant- Sold
1986 Merkur Xr4ti- abandoned
various mundane American autos

If I'd known then what I know now...

Hell, I'd probably still have done it anyways.