Originally Posted by Rsickles

The Speed version of the short-stroke crank is the most expensive part of a Speed... but also where the biggest power gain comes from. Most of the power comes from enlarged crank opening and the ramping on the back.

Correct me if I'm wrong, but Arrow fixed the biggest problem with the standard VSpec and got rid of the oiling hole on the crank pin and moved it to the rod instead (like on the Speed version). Helps with crank pin wear (minus DLC).

Assuming the crankcase exhaust port is identical, the one thing I think Arrow could do is start using a Speed VZB version sleeve. There's no extra work (meaning, no extra production cost... just initial setup costs)... it's simply altering the exhaust port shape. The improved exhaust cutout on the Speed sleeve helps a lot with mileage too.