OK guys, i cant quite get my head round this...

on ym car i'm going aftermarket, and it'll me mapped with RPM vs TPS only (2D?) now i'm told that i won't need a map sensor input (3D?). now, i'm sure this isn't the proper way to do it, because why else would nasp cars come with map sensors... however i cannot think of a good reason (or any reason) why RPM vs TPS wouldnt be sufficient, as in a non-turbo car, surely map would be never change at xxx RPM vs yyy TPS

the only thiing i can think of it making a difference would be load in different gears or up hills etc.

can anyone help me get my head around this?

ps i will be wiring in a map sensor with my new ECU regardless of its its used or not, and if it will be usefull to use it in the map, i will

ta

Jim