The whitest halogen bulbs in the market are Philips Diamond Visions. They sacrifice lumen output though and aren't street legal which is why you can only find them online. You'll also want to watch out for counterfeit as they are popular. If you want street legal, crystal visions are ok, but you're back to a fair amount of yellow injection as itsi just physically impossible for those halogen bulbs to reach high enough temp range at that wattage. The best solution is an HID kit, but understand if that's not the direction you want to go.