Like the title states whats the difference between the version 4 5 and 6 as for as motor, tranny, ecu, power?

i dont car about the car itself i can find plenty of info on the rest of the car...

the motor will be going into a 95 or 96 impreza...

thanks A ton

start here
http://www.catherineandken.co.uk/sti/wrx.html

i would highly recommend the 95 vs the 96 as its obd-1

ok so if i went with a version 6 thats obd 2 a right? but it doesnt give me like what does the ver 4 rev out to and what does the ver 6 rev to? and why is this? and as for as tranny it doesnt say if there the same... sorry im just trying to get to the bottom of this wiring doesnt scare me really and i am after somthing with a little more power from the factory you so i can just do the little stuff its kinda a track slut ;) and want a more reliable factory power but

that was pretty good info but not quite what i want you got any thing else? i have been at this for 2 days...

no nothing jdm is obd-2 even the brand new stuff

depends on the model, a standard 4/6 is 7500 the sti RAs are 8500

www.garagetuning.com is a great source for your questions, they're a Subaru swap shop in CA.

Ive driven ver 3, 4 and 5.. out of the those i liked the ver3 best.. dont know why.. but it felt more "raw" above 3 were in stock trim.