and interceptors? DatEdit says 1 but that's obviously not right.

so is there another way of knowing the cooldown is between attacks of reavers and interceptors?

Starcraft.wikia.com has these unit's stats, I think. I seem to recall that the Reaver's was 60, but I doubt that.

Reavers fire scarabs. The reaver firing the scarab is considered Reaver Cooldown.
Scarabs have timed life. I'm not sure if this is considered a cooldown, but they eventually just pop.

ok so wat about incerceptors

I think 1 is the cooldown for releasing interceptors. Try looking up Pulse Cannon in weapons.dat. I can't do it right now because my comp broke down.

The rate of interceptors attacking is mostly based on its AI action (which is pretty badly hardcoded). It simply moves around and goes in on "bombing runs" to attack, then escapes back out. The interceptor will only attack usually once/twice on each "bombing run". Ive tested this by giving the scarab the exact data from the archon and giving it intercepter AI actions . The "archon" would run around and attack only once/twice per run (not to mention it would return to the reaver after attacking). There I dont think theres much you can do about the interceptor attack rate.

Extra info: I doubt scarabs themselves actually have a timed life (the archon scarab didnt die automatically). I think its AI related. Also, the reaver cannot have two "minions" outside at the same time.

Also to note, interceptors with damaged HP return to the carrier and get repaired when inside it.