There is a long list of benefits allied with upgrading to HID headlights. They emit brighter light, and this enhances your safety when driving at night because you can see better. These lights also draw less power from the battery and have considerably longer lifespans when compared to standard halogen headlights.

HID conversion kits are not new in the markets, although their demand and popularity have increased dramatically over recent years. You can find these units in a range of types and designs, so it takes a bit of research and patience to find an ideal product.

HID ballasts typically operate at a power of 35 or 55 watts. Besides the obvious difference in the wattage between these two options, there are other vital differences we will discuss in this post.

Similarities Between 35W And 55W HID Conversion Kits

35W and 55W kits are closely related products. They share several similarities, including the fact both kits come with lamps that last between 2-3 years. These lamps are made of anti-UV Quartz. They are also 100% wind and water-resistant.

Moreover, both kits need a relay harness kit if they are to be installed on a car with daylight running lights that are on a similar beam as the HID lamp. The 35W and 55W kit both come with extra wiring (typically 28 inches), casings and cables that are designed to prevent electromagnetic interferences.

Differences Between 35W And 55W HID Conversion Kits

Let’s dive right in and get a better understanding of a few prime aspects that will help us settle the 35W vs. 55W HID kit debate.

Wattage and Brightness

Let’s take a look around one of the main differences between 35W and 55W conversion kits: the wattage.


35 watts are the standard output of most units in the market, and their brightness ranges between 2300 and 3500 lumens approximately. These are the kind of bulbs that are commonly factory-installed on luxury cars. The 33W bulbs are about three times brighter than standard halogen bulbs.


  • Runs cooler
  • Draws less power
  • Eliminates color washing
  • Are 3 times more luminous than halogen bulbs


  • Most kits do not allow mounting outside the headlights without a few modifications


55W kits have a higher power output, and this makes them brighter. They produce 4-5 times more brightness than halogen bulbs and are estimated to have an intensity of 3000-4800 lumens.

This makes them a top choice for anyone looking for maximum brightness. On the downside, 55W HIDs may cause excessive glare.


  • More lumens
  • Brighter light


  • Prone to color washing
  • Prone to overheating
  • Shorter bulb life
  • The light produced can be too intense for some motorists


Overheating is one of the significant downsides of using a 55W conversion kit. Usually, HID bulbs run cooler than halogen bulbs, although 55W kits are prone to producing high amounts of heat that can melt the wiring and housing.

If you want to enjoy the perks of a 55W kit, make sure your headlights are made of metal and not plastic. Additionally, upgrade your plastic plugs to ceramic plugs because they can withstand the heat better.


35W kits are uniquely designed to produce adequate brightness and still run cool. On the other hand, 55W kits are prone to overheating, although they provide maximum and more superior light output.

This higher wattage and increased heat cause more evaporation of gasses and electrodes, cutting short the lifespan of 55W HID conversion kits.

When properly installed and used, 35W HID conversion kits could outlive your car. 55W kits typically last longer than halogen bulbs, although their longevity is shorter when compared to 35W kits.


Another crucial difference between 35W and 55W kits is their color output. For instance, 6000k appears different on the two units, even if they are sourced from the same manufacturer. 55W kits are unfortunately prone to color washing, and this means that 6000k will only provide a 4500-5000K color output.

But there is a catch; washed-out color is still acceptable because it appears whiter. Well, white is considered the best color for proper human eye vision. It also tends to function exceptionally well within poorly lit areas.

Even with overheating problems, it still makes perfect sense to choose 55W kits. Just choose to go a little higher in terms of HID Kelvin temperature because this will reduce the heat output. A 12000K HID conversion kit with 55 watts produces the same heat output as an 8000K HID kit with 35 watts.

Final Words

What is apparent is that both 35W and 55W kits have their unique pros and cons. You must study these perks and downsides carefully and figure out which unit is best for your needs.

Some say there are good reasons why high end cars come with HID systems that have a 35W rating. It is also safe to say that there are equally great reasons why 55W kits are in higher demand. In the end, the most important thing is to choose a kit that best suits your primary needs.