ok so thjnking of converting my halogen lights to R2s, I can fit 3 into my existing head unit, i run a 6volt lead acid battery. Would 3 leds be to much and if i use 3 what sort of run time can i expect?
The cutter mr11 triple or quad led kit will fit. You would need a "boost" power controller to use with a 6 v battery. Run time is dependent on the amp / hr rating of the battery and the current you run the leds at (0.5 amp - 1 amp)
3 leds runs at 11.1 Voltish so would be inefficient even with a boost controller but would work
Runtime at 1 amp would be battery voltage divided by led forward voltage times the amp /hr rating of the battery minus a bit for inefficiency - say for a rough guess half the amp / hr rating of the battery. So a 2 amp / hr 6 volt battery would run 3 leds at 1 amp for about an hour.
There is a run time calculator on the Cutter website
http://www.cutter.com.au/index.php