found these

[budweiser]

found these http://www.ebay.co.uk/itm/3902230928...#ht_2704wt_952
but dont like the ££, then i found these
http://www.ebay.co.uk/itm/1707089633...ht_3383wt_1185
wil they be same power? bright wise 10w=100w
im thinking to remove the light bulbs of my 2 lamps and try these on, but they are up to 11v what else should i need? resistors?

[Apache]

Start by ignoring the 10W = 100W bullshit. 10W is 10W, 100W is 100W.

What they're trying to say is their 10W LED produces as much light as a 100W halogen. That may or may not (probably not in my experience) be true. What they forget to tell you is a halogen bulb produces light nearly isotropically, whereas an LED produces it's light over a fraction of that angle.

Those LEDs you pointed out are for a forward voltage of 10 to 12V, which means they'll not last long on 14.4V. So, you'll need to drop ~2.4V across a resistor. With high power LEDs, this isn't the way to go. A better solution would be to build or buy a 12V regulator suitable for >1A - if you're using multiple LEDs then the current will go up accordingly. This means that whatever the output of your alternator, your LED will only ever see up to 12V.

Then you need to factor in that the light dispersion from the LEDs is only 160 degrees, not nearly isotropic as per a conventional bulb, and choose your reflector accordingly.

Interesting if you fancy a winter project, but not a 5 minute plug and play job if you want to achieve something worthwhile.

[Kiwisurfing]

Apache is right on all accounts about the regulator, plus they are to expensive to risk running on a resistor.

But just gotta add, Ive seen some proper jobs on L.E.D lighting on 4wd's and they are amazing what they can put out and for such little power requirement.

Even the warehouse where I work is trialling some brand new L.E.D lighting, for 50 watts of power they are putting out the equivalent light as the older metal halide lamps that consume 430 watts

And ranting on again sorry, I also have an L.E.D torch that is somehow brighter than the headlights on my surf????? Crazy technology around

[Apache]

That's what I was alluding to. The technology is very good, but you can't implement it as you would a conventional bulb and expect it to work optimally.

I have a Hope Vision bike light. It's the size of a D cell, produces 400 lumens, and lasts a couple of hours on 4 x rechargeable AA cells. Stunning!

[budweiser]

mmm!! my idea was to use 5 lamps on the roof rack using less power from the batt.
but for wat you posted is not viable, or im getting it wrong?

[Apache]

If your engine is running, you shouldn't be using power from the battery. If you are, there is either a problem, or your alternator is too small.

Not saying you should not do it, all I'm saying is it will require more work than plugging them in to some reflectors. Would make a nice winter project though, and if done properly, could be quite impressive.

[Ambobeer]

This ought to sort out the regulation issue
http://uk.rs-online.com/web/p/linear-regulator/6869669/

Might need a few mind.

[Vultch]

I'm still trying to find a tug toner on eBay

[Apache]

This ought to sort out the regulation issue
http://uk.rs-online.com/web/p/linear-regulator/6869669/

Might need a few mind.

Yeah, that'll do fine. Get them from Maplin for probably half that. I'd use one per lamp, fitted in the housing. Nice and neat. 7812's don't strictly need any external components either, though I might stick a low value cap on the I/P and O/P.

[wishbone]

Maybe use conventional spots and buy an HID conversion for them.