Better Machining = Better efficiency

[slowmover]

Diesel pickup engines are already at 2X or more the price of a gas motor for the same vehicle (longblock crate motor replacement). Machining is part of this discrepancy.

[YeahPete]

What kind of mileage gains are estimated for something like this? 5%-10%?

[slowmover]

That gasoline motors no longer consume oil (1/qt per 500-miles was common for a 1980s and earlier big block) is part & parcel of better machining (not just better design, though that would be most of it), so the overall effect is not just limited to fuel burn. Other components can be made with tighter tolerances, for one, and even cooling systems be made smaller as the engine is under such fine control. Best machining is almost ice on the cake.

Controlling what happens in the combustion chamber is almost super-computer stuff . . so the direction in which to take steps is now more clear.

[oil pan 4]

Originally Posted by YeahPete

What kind of mileage gains are estimated for something like this? 5%-10%?

I used better, tighter and different tollerances to help with fuel economy and it didn't seem to give me any huge gains.
So I would say its well with in 5% to 10%.

I didn't go full race motor prep but I went way beyond a normal stock rebuild.