What to look for in a motor? woofer building

[P4killer_]

Ive always wondered this..

The motor seems to be the most important item in building a woofer. Its always the most expensive.. and I always come across custom woofers that use the same coil, however the woofer with the 4hp motor over the 3hp motor for example has alot more power handling. Im assuming a stronger motor means more rapidly moving coil through the gap Ie: more air pressure = better cooling = more power handling??

anyway, I would like to build a woofer for fun or recone some motors i have lying around..

what do you look for in a motor? Are there any direct sources for obtaining soft parts and coils etc.. or do you just wait for em to pop up on caco> or something?

i know psi sells parts, but how do you know if a 2.5inch coil fits your motor? whats an acceptable clearance? like if the gap measures 2.567in and the coil is 2.56in is that too close? what if its like 2.45 in is too much space an issue?

that kinda thing.

Thanks in advance.