Great pics of that powerplant, just sick - great bud structure!
Here's a few I've run under 400 watts of light:
DAMN you got some sweet looking ladies there. What are you feeding them?
where'd you get that cooltube?
84 would be as high as i would go personally. i run 76 lights on/68-70off in my GL80 w/ a dayton 265 cage fan (out of a lil furnace hahaha). until i got that fan i usually ran around 82-84 lights on 75 lights off with no ill effects. ive heard people say some strains can take temps into the 90's. you should be fine