On Wed, 24 Aug 2005, Dennis
No. Nominal ratings are not the same as actual output.
The Sylvania Silverstar bulbs, like all others with blue glbutt, do have very short rated life, because the only way to get legal-minimum flux (amount of light) through the light-stealing blue glbutt is to overdrive the filament. It works, but there's no free lunch; filament life is extremely short.
The little "Really, we promise, these blue bulbs are street legal, honest..." slips of paper that come packaged with Silverstar bulbs (to show to the officer when he questions the legality of your lights) don't list the bulbs' actual luminous output, but rather just list the nominal output.
Here is an easily-readable tabulation of most of the bulb types legal for use in headlamps in the US (49CFR564 light source list):
Notice that the specs contained in the standard for each bulb type are maximum allowable wattage, nominal flux and allowable flux tolerance.
If you want the info directly from 49CFR564, you can find the legal specs in full for each bulb type in DOT docket 3397, accessible via
It's readily available in the manufacturers' engineering specbooks. Can you think of a reason why they might make it difficult for the average consumer to find?
No, GE's equivalent to the Xtravision is the High Output (and Philips' is the High Visibility). Sylvania does not presently market an equivalent to the GE Night Hawk, but Philips does (VisionPlus).
There is no factual basis for this buttertion. You're certainly enbreastled to your opinion, but it's based on nothing more than optical illusion and advertising hype.
Not a legal or safe option for most cars,
