I think the fillament arrangement etc is the same.speedy231278 wrote:By 5 watts I was referring to having 60/55s fitted and 5w a side difference from going low to high beam (so 10 in total). Now I've twigged the difference in the filament arrangements I understand why these 5 watts per side with the wrong amps could have seemed to make so much of a difference. So, yes, 20w per side different with the correct ones fitted. I assume that the filament shielding is different too, and why the low beam actually appears better with less watts from the right bulb than with more from the wrong one!
I think it is a question of what bulbs you are using. There are not so many cheap copies of the H4R bulbs (the 60/35w) so you probably have a higher quality bulb than your regular H4.
For your power equations (this is of course approximate and will vary due to bulbs / wiring condition etc etc)
Original Spec (60w/35w H4R Bulb x 2)
Low beam: 70 watts (5.8 A)
High beam: 120 watts (10A)
H4 Spec (60w/55w)
Low beam: 110 watts (9.2A)
High beam: 120 watts (10A)
You can see the high beam load doesnt change. However, by using H4's over the stock H4R you are consuming an extra 3.4 A of current (58.7% increase over stock)
If you goto the trouble of H4 and a relay etc get some good bulbs. Philips Extreme are fantastic bulbs. Unbelieveably bright for stock wattage.