Has anyone ever used 100W bulbs in their H1 lights with no change in relays in a SWB car with any bad effects?
John
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Has anyone ever used 100W bulbs in their H1 lights with no change in relays in a SWB car with any bad effects?
John
My experience is hearsay only, but have heard stories of smoking headlight switches from continued running, if relays aren't used. They just aren't designed to run that much current.
Thanks Kenikh,
I'm trying to find out if it's some kind of urban legend.
John
If you could measure the gauge of the wire going to your
dash switches you could determine if they could handle
the current safely.
With 200W the current will be 16 amps.
I'm sure the EEs here could work it out just by measuring the
resistance of the wires. Bigger gauge will be less resistance
which will result in less heat.
I don't know what your dashboard switch is rated at (might be
printed on the back side). A quick google suggests 12 gauge
wire for a 20A circuit although that pertains to household wiring
and I don't know enough about how or if voltage affects this
calculation.
andy
I've read the resistance calcs somewhere, but only recall they reinforced the decision for a relay. . That said, the only proof I needed was looking at what the stock bulbs had done to my swithc over a lifetime. Afetr spending a day trying to my lights up to snuff, tracing wires, cleaning grounds, changing fuese...you name it...I finally added a relay. Guess what, mega bright lights. Further inspection showed that full current in switch had pretty much eroded all of the contacts, reducing current flow to jack sh--.
Net net, may work on a new switch, may work for a good while, but the risks aint worth it IMHO.
Hi John,
No legend,...100w bulbs will eventually ruin the low-high beam switch contacts so relays are strongly recommended since they are far cheaper than the bloody switches.
Thanks guys...thats all I need to know.
John
John,
For sure, put in relays for 100w bulb operation. It is fairly easy.
-Allen-
wow, this goes back to my days in the German Army...
I had a 69 911 T and upgraded it with and RS spoiler, hood lamps and Cibie foglights.I was driving at the time also some local rallies.
So I put 100 W in the hood lights and in the high beams of the headlights- at that time highly illegal to the TUV.
So when you drive at night on the Autobahn at high speed I had the headlight on, if someone tried to come with a lower speed into my lane I warned him with the foglights....no reaction, here go the hi beam headlights...still no reaction here yopu get it full Cibies with 200 W....I know sounds rude and aggressive, but I was 19 and that was the German Autobahn Wahn or war....never smoked the switches or the alternator...amazing in retrospect.....PS it worked.....
I had a '79 Turbo. I put 100 watts in the HIGH and LOW beams, H1s, both on relays and also with an extra switch. I could turn on the driving lights and High and low beams and ALL at the same time if I wanted. Really lite up the road, which in a Turbo can be very necessary.Quote:
Originally Posted by GTS
-Allen-
H1s with 55W low beams and 100W high beams for 4 years. No relays and no problems, but my high beams are only on for a few minutes at most.
That being said, I plan to add relays. As the saying goes, an once of prevention...
My 1.5 cents.
JP
Quote:
Originally Posted by kenikh
How and where did you add this relay?
It's not just urban legend. I went through this with the *optional* 100W bulbs for rectangular Cibie driving lights. Not recommended without intervening relay, due to high current loads. In round numbers 100W @ nominal 12V = 8.3 amps. Two of them = 16.6 amps.Quote:
Originally Posted by John Straub
- MR
Where's John Cramer when you need a short answer to these sort of questions ;-)
Have had H1s with (4) 100w in all my 911s for over 30 years... Never had a problem and never used a relay... Just lucky I guess...
In reality they are not really drawing a 100 watts... More like 65-70...
Added 80/100s and not only added fused relays, but ran complete sets of higher gauge wire to new ceramic connector plugs (read: Non-melty). It may be overkill, but I can run both beams without worry or regret, and the light ain't bad either. But then I added driving lights too and... ;)
I am adding relay(s) to my headlight circuit. What I need to know is can I keep the original 14 gauge wiring size when I redo my harness. I assume so. The point of the relay is to avoid the current from having to flow through the switches. Doesn't seem like undersized wiring is an issue, is it?
Exactly my situation, highs only for vey short term or flashing... No issuesQuote:
Originally Posted by John P
I've had H4s with 100/55 bulbs in my car for over 15 years without relays. Same T/S switch since new and no problems for the last 40 years. I would recommend relays, though.Quote:
Originally Posted by Bummler
Do as I say not as I do.
Regards
Jim
Seems a no-brainier to add the relays, I've done it to a few of my cars, and 2 of the cars had new headlight and/or turn signal/high-low beam switch replacements before I bought them, so the added relays help protect the expensive switches. The relay installation takes only a few minutes, is completely reversible if you ever need to attend a concours event....seems like great insurance, and only costs a few bucks. Simply a matter of pulling the low and high beam triggers off the fuse block, and running the relay outputs back to the same spot...plus power and ground direct off the battery.
I know... Frankly it's just lazinessQuote:
Originally Posted by Jim Breazeale