Dynamic sound for vehicles

Currently i am trying to make the sounds for my space combat game, but i don't know how to go about making the engine sounds. Obviously the engine will sound different at different speeds. Do i make one sound and through scripting alter the pitch and stuff (i'm not a sound guy). or do i just record lots of sounds at different speeds and play them when and where (also if you are suppose to do it t$$anonymous$$s way how would i blend them together).