No energy savings with 35watt HID's !!!!
 

So I heard a rumor that all aftermarket 35 watt hid's simply have a resistor to output 35 watts- this means the system is still using 50 watts because of the resistor.

In other words, your better off going with 55 watt hid's because you get all the wattage in light output instead of light+heat in the 35 watt hid's.

Thoughts? True or not? Anyone that can test this in their car if You have aftermarket hid's?

LOL no
Not true.

Normally, when someone asks a question such as this, and you answer it, you'd do so with a reference...

Well the reasoning behind it is to fool the cars ecu into telling it that there is still a bulb there (since it's using less watts some cars might throw a code).

Again, just rumors I've never actually tested a ballast before with a multimeter.

Well, you need a question mark instead of four exclamations in the title, but I couldn't imagine a 3A headlamp in place of a 5.5A one would create any problems bigger than a "bulb out" warning light. Maybe some HID makers install a resistor to draw extra current, but I doubt it. Write to the manufacturer you're thinking of buying from, then post their response here. I do know the fancy headlamps on the Prius draw less than 55W, which proves that such lamps are out there.

*blink* *blink*

Headlights are basically just a simple DC circuit... Think V = I x R and P = V x I

The 35W lights should have higher resistance which means lower amps. Power is thus reduced because the amps are lower, the voltage has stayed the same (nominally 12V).

However, in the grand scheme of things, it's almost irrelevant. Saving 20 watts x two lights is 40 watts. 745watts per hp, so you're saving a whopping .05hp by switching lights. I'd rather have the better lighting.

Mike

Why would anyone need a bulb out idiot light. Looking out the windsheild and half the road is dark is a pretty good indicator.

People are becoming dumber and dumber every year, that's why.

It's not so much an idiot light, but that the ECU will note a fault code if a circuit's not measuring up as expected.

It's an engineer's mind on thoroughness, when they already include an ECU code for high/low/no voltage on engine sensors, to extend the same to other circuits on the car.

Thats why you get one of these.
Error Code Eliminator - 3 (PAIR): DDM Tuning - HID Kits, HID Bulbs, DEPO Lighting, BMW and Porsche Performance Accessories
:thumbup:

^ and how do you think those work?!

By a resistor ... Thus wasting the same amount of energy ... See what I was talking about now?

A lot of people do most of their driving in cities, and with streetlights & other traffic, it can be pretty hard to tell if your lights are on at all, let alone whether one is out.

Regular and/or pre-trip equipment checks would remedy that situation... so it's still on the head of the driver when something goes out. It's part of vehicle ownership/maintenance to regularly check for these things.

This is why a cop can ticket you for a light being out, even if you claim you didn't know. You really might not have known - but you SHOULD have.

I really hate it when people make excuses for laziness.

Again, for a simple DC circuit: V = I x R and P = V x I

Or, to put it another way P = V²/R.
So, with constant voltage, as resistance increases, power decreases. Adding a resistor reduces the power used.

Mike

Removing the bulb out idiot light from the dash works just as well. You're making a mountain out of a mole hill.

40W is miniscule; true. But HID lamps deliver more lumens per watt, so a 35W HID is as bright as a 55W halogen. Also remember that 40W is 0.05HP of pure electricity, which takes about 0.1HP at the alternator shaft. If you do an enormous amount of nighttime driving, or if legislation requires that you drive with the headlights on, you stand to save a few gallons of gas a year.

OP was comparing 35W HID to 55W HID.

I'd still rather go with the brighter lights if I were doing lots of night driving. Saving a small amount of fuel isn't as important as improving your ability to see where you are going.

Mike