It's Easy To Overdrive Your Headlights In A Porsche



It's way too easy to overdrive your headlights in a car like a Porsche that is just such a pleasure to drive fast, especially at night for some reason. Maybe living in Central Oregon makes me more sensitive to that fact than those in more urban areas as we have a lot of critters roaming around at night. I don't know anyone who hasn't hit a deer, thankfully it's usually in an SUV or a truck as it can get pretty serious in a Porsche.

Avoiding Overdriving Your Headlights

It's simple math. If you're driving at night with H4 headlights you should probably think about keeping it at 68 mph or lower. That gives you a margin of 42' - you see an object at 350' and it takes you 308' to stop.

With LED's you can move safely at a bit less than 80 mph. At 80 mph you have a close margin of 11' - you see it at 450' and it takes you 439' to stop.

Bottom Line: It's not safe to drive over 70 mph at night with H4 halogen headlights.

 Stopping Distances


 Illumination Distances

JW Speaker 8700 Dual Burn LED's
Halogen H4 High Beam Range: 350'
JW Speaker LED High Beam Range: 450'
Halogen H4 @ 70 mph - Safe? 2' to spare
Halogen H4 @ 75 mph - Russian Roulette
JW Speaker 8700 LED @ 70 mph - Safe with 105' to spare: 455'
Speed Limits To Avoid Overdriving Your Headlights
H4 Halogen Bulbs: 68 mph
LED Assemblies: 80 mph

Note: These are approximate numbers. You be the judge.