Bought new upper control arms but they werent marked left or right anywhere i looked...if i just put them on will it be ok if they are backwards?

 

will not be okay if you put them on backwards. you have to make sure they are on the correct side, or your caster will be off.

do you still have the old ones on the car? if you do, just match them up

 

the old ones werent marked either and looks (to me) identical when placed side by side..... the boxes the new ones came in have no part numbers or else i would look them up...

 

well, if they match up... you might be lucky and it might not matter. but even acura has it listed as a right and left....

 

It does matter which side they are installed on. They aren't symmetric.

Swapping the UCAs left to right will add 1.5° of caster, taking the car well out of the factory alignment specifications and reducing the available bump travel (the UCA hits earlier than it should).

I did that on purpose, and now have dented shock towers...