No lads, when using timers for HID lights you need to pay attention to the inductive load value as this is the load that ballasts pull as apposed to resistive load that oil heaters and regular appliances pull.
"Normal household timers are not built to take the high inductive loads produced by HID ballasts. If used with an HID ballast, the contacts inside the timer that open and close the timed circuit will overheat and weld together, breaking the timer and leaving your grow lights permanently on."
So that timer you have Garry is only really suitable for running 1 400w light and a fan if the inductive load is rated at 480w, there are cases of people using under rated timers for more wattage but I personally wouldn't advise it and any sparky worth their salt will say the same, also if it burns out and sets your house on fire you've only yourself to blame lol.
If you use the Plug and Grow ones off Ebay (£12 ish with free delivery) they will run 2 600w lights each, the good thing about the Plug and Grow ones are that the internal contacts are rated for 22A not just the fuse in the plug @ 13A.
Plug and Grow timer.
http://www.ebay.co.uk/itm/PLUG-AND-GROW-HEAVY-DUTY-TIMER-SWITCH-600W-GROW-LIGHT-/270732866707?pt=UK_Baby_Baby_Feeding_Bottle_Warmers_Coolers_LE&hash=item3f08efb493