Even with the Mitsubishi CAPS parts system, this particular one is kicking my behind. Am trying to find the part number for a set of Evo I pistons (although the same is true for all Evos), and the CAPS is giving me 7 different sets:

STD A: MD300034/MD313285
STD B: MD300035/MD313286
STD C: MD300036/MD313287
O/Size: 0.25: MD300040
O/Size: 0.50: MD300041
O/Size: 0.75: MD300042/MD313291
O/Size: 1.00: MD300043/MD313292

What I want to know is: what is the difference between the the STD A, B and C pistons? Am assuming there are just tiny differences in size in the pistons that occur from day to day in the factory, but could I put, for example, a set of STD B pistons into a car that previously used STD C pistons?

All very confusing.

 

i'm gonna guess judging by the part numbers A is a 85mm piston, b is an 86mm piston and C is a 87mm piston. you can't usually just drop pistons in, most of the time you need some machine work. Okinawa? you live there, or stationed there?

 

See that's different from what I've heard. Some others have said with the A, B, and C you might be able to drop right in.

Yeah, I live in Okinawa. Been here 4 and a half years now and loving it.