AndrewM

Anyone BTDT? Any problems with the stock wiring? Finally have my PDAS/ABS problem fixed, bad coil BTW, and my 89 C4 with the 3.8L conversion (with 993 cam towers, hydraulic lifter's for me) is so fast that I need more light!! LOL
Drew
89 C4
86 930

Ruairidh

[quote]Originally posted by Andrew Muzychka:
<strong>Anyone BTDT? Any problems with the stock wiring? </strong><hr></blockquote>


Drew,

Common wisdom has it that you'll fry your electrics if you go to 80-100 without a relay. There are a number of threads on this subject but, alas, no step by step guide as to how to insert a relay in a 964 (as opposed to earlier 911)

FlyYellow

Drew,

Here is the math behind the electrical capabilities of your stock wiring.

80watts/12volts = x ohms

this means that at 80volts with 12 volts power you draw 6.67 ohms

your stock fuse should be 7.5 ohms or 15 ohms combined for Left & Right headlights. SO with that said 80watts is fine.

Now if you apply the same with 100's

100watts/12volts = 8.3amps. So there lies the problem. This will blow your fuse and if it doesn't will certainly overload your wiring. So a simple solution is to get 80w/80w for both lo & hi beams. That will be fine and will produce noticeably more light. Don't waste your money on the blue / white / xenon fakes they do not produce more light on the contrary less. I would however recomend halogen bulbs by philips.

Lastly, short of a HID upgrade I would recommend H4's. If you want to see what light they produce you can see them on my 964.

Cheers,
Boris

AndrewM

Thanks guys..
I to looked for a step-by-step procedure for wiring in a relay for the 964 and could not find one. Looks like I'll go with Boris's advice and fit a 80/80 bulb. The only question I have is do they make this combo? I'll start searching in the usual places...
BTW, just finished washing and waxing the C4 in my buddy's heated garage. Couple of guys talking cars, having a brew.... Life is good!!
Drew
89 C4
86 930

ckkrause

I think you'll find that going to an 80 watt H5 bulb will not make appreciably more light than the 55 watt bulb becuase of the voltage drop on the inadequate sized stock wiring. The wiring in the stock lighting circuit is about 18 gauge and to get the full capacity of the 80 or 100 watt bulb on the road, you need to go to a relay system and use 10-12 gauge wiring in the power circuit. The relays also prevent overheating (and a voltage drop) across the light switch terminals. The hard part is finding H5 sockets that have or can accept 10-12 gauge wire. I'm looking for such sockets right now. Good luck!

-CKKrause

FlyYellow

Ya, I agree that 80watts on a H5 may not do much. Although I think it has more to do with the lousy design of a h5 than the wiring. I don't think the wiring is 18 gauge (that seems way too skimpy - I would have thought it was 14 - 16 gauge).

I really would urge you to go to H4's with the trim rings. They look really nice and it is a distinctive look a 100 yards away.

Also to get relay harnesses and installation instructions go to <a href="http://www.suvlights.com." target="_blank">www.suvlights.com.</a> They sell the relay harness cheap. I will tell you it is really easy! If you need help just shout.

Cheers,
Boris

Ruairidh

[quote]Originally posted by Boris Teksler:
<strong>

Also to get relay harnesses and installation instructions go to <a href="http://www.suvlights.com." target="_blank">www.suvlights.com.</a> They sell the relay harness cheap. I will tell you it is really easy! If you need help just shout.

Cheers,
Boris</strong><hr></blockquote>

Hi Boris, could you check that site, it doesn't work for me. Incidentally if anyone does do a relay, please could they post tips on this site as I think it is a frequently seen issue.

eion

Just delete the full stop from the URL, <a href="http://www.suvlights.com" target="_blank">www.suvlights.com</a> works for me.

FlyYellow

here is another set that you can purchase....

these are the regular 70watt (which you will not need any relays for):

<a href="http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-no-1541-none.cfm" target="_blank">http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-no-1541-none.cfm</a>

or if you really want the blue look and accept less lumens output then...
<a href="http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-No-814-none.cfm" target="_blank">http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-No-814-none.cfm</a>

for the wiring kits go to:
<a href="http://www.nextcollection.com/html/ORD-Light~bulbs-Heavy~duty~Harness-No-4671-none.cfm" target="_blank">http://www.nextcollection.com/html/ORD-Light~bulbs-Heavy~duty~Harness-No-4671-none.cfm</a>

P.S. I have no affiliation with this place. Although I have ordered there stuff before - they are the cheapest place on the 'net I found.

Cheers,
Boris

BarryG

[quote]Originally posted by Boris Teksler:
<strong>here is another set that you can purchase....

these are the regular 70watt (which you will not need any relays for):

<a href="http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-no-1541-none.cfm" target="_blank">http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-no-1541-none.cfm</a>

or if you really want the blue look and accept less lumens output then...
<a href="http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-No-814-none.cfm" target="_blank">http://www.nextcollection.com/html/ORD-Light~bulbs-Heliolite-No-814-none.cfm</a>

for the wiring kits go to:
[URL=http://www.nextcollection.com/html/ORD-Light~bulbs-Heavy~duty~Harness-No-4671-none.cfm]http://www.nextcollection.com/html/ORD-Light~bulbs-Heavy~duty~Harness-No-4671-none.cfm[/ URL]

P.S. I have no affiliation with this place. Although I have ordered there stuff before - they are the cheapest place on the 'net I found.

Cheers,
Boris</strong><hr></blockquote>

Also, do a check on reviews of bulbs. You should find the brightest lights you can buy short of HID are the Sylannia Silverstar bulbs. They are about $24 each but they a very bright and very white. You will not need a harness for these.

Barry

1990 C4 Cab

FlyYellow

Barry,

I couldn't find the silverstars in the 70-85 watt range. That's why I went with the Heliolite bulbs instead. I do feel obligated to say that you do not want the silverstars with the silver tint! you want the clear ones. I will also mention that I don't believe a 55watt silverstar will produce more lumens than a 70watt heliolite (regardless of the 50% brighter claim). I would love for someone to prove me wrong on that one.

Cheers,
Boris

AndrewM

Thanks Boris!!
Drew
89 C4
86 930