ReFuze fuse box installation experience (modern fuses)

[GregVandenbussche]

Here is my experience installing a ReFuze fuse box on my (definitely not original) T5.
I do not have any afiliation with CddAutogear. I'm planning on doing a similar article on the Stoddard/Magnaflow ss exhaust when I find the time.

My car is not a trailer queen, the only thing original to the vin is the body under 3 thick and of questionable quality layers of brown paint, it is being driven often and hard.
It has endured many modifications during its life and a lot of them done poorly by previous owners in the 70’s
(I mean, who would paint a fjord green car in brown and install orange shag carpet?)
Car was also converted to 12 V and wiring harness is mostly custom made with wrong colors and simplified wiring for things like headlights/taillights etc...
That being said, I had a few electric gremlins with it and was getting tired of the glass fuses installed in the previous non OEM fuse box with no cover.
Modern fuses are much easier to find in any gas stations in the middle of nowhere (where we usually find ourself driving), my options were to source an original fusebox or get a modern one, latter option made the most sense to me.
Enough said, here is my experience with the fuse box:

Box arrived accompanied with a cover / knob screw, zipbag of small zip ties, 1 extra knob and screws, 2 bags of Fuses (7.5-15-25) and a small manual with some usefull info (mostly for cars with stock wiring).
box is nicely built and feels really solid.

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I proceeded to remove this ignominy of a rat’s nest:

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After tracing all the unknown wires (all of them), removed the old connectors, I connected the wires easily to the new fuse box using the brass screws. There is 3 banks i’m not using as i do not have a relay for lights etc...
The ReFuze is internally wired as the original box, and it fit perfectly in place (I used the old screws as someone re-threaded the mounts using non metric slightly larger size):

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The cover fits tightly, is looking good and it will prevent shorts

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I now have had the Refuze box in the car for the last 6 months with no issues or blown fuse nor fried wires ,

that being said if anyone has recommendation for fuse rating/circuits I would be interested to hear them, LED front and rear lights

[Geoff Fleming]

Looks like you did a nice job with the new fuse box. The one you replaced was not an original anyway but a fairly modern box from who knows where.( Only eight fuses, should always be twelve.)
I'm always 'impressed' when I see 356s with electrical systems 'improved' upon by some weird prior owner who apparently knew more than the engineers at Porsche. Glad you updated your car.

[GregVandenbussche]

Thanks Geoff! so many things are wrong on the wiring harness, would like to get my hands on a reasonably priced original one at one point. Still need to figure out why my reverse light doesn't work

[David Green]

Hi Greg,
I'm not sure about the T5 but in the earlier cars the reverse light circuit runs through contacts in the high beam switch that you might want to check. Also I use SMD headlights (very bright and draw very little current) and CuLayer LED brake lights. Both discussed on the forum.
David

http://culayer.com

http://www.classicowheels.com/specialtyparts.htm

[GregVandenbussche]

thanks for the tips!

i'm also running similar front and rear, and same battery since 6 years!
my last sentence on the first post was for indications on load if anyone has advices for fuse rating

[Craig Richter]

Since your car was converted to 12-volt and you are using LED lights, 7.5 amp fuses should be enough everywhere, except perhaps the windshield wipers depending on how the PO did that tricky part of the 12-volt conversion.

[GregVandenbussche]

Thanks Craig! makes sense!
Actually that part of the conversion wasn't done cheaply, the windshield wiper motor is 12V, same for all the gauges!

[Michael Branning]

I recently measured the Classico LED lights I won at the Helen auction. With a bench supply set to 12.0v and 6.0v (per headlight):

12v hi - 0.62a
12v low - 0.42a

6V hi - 1.22a
6V low - 0.83a

[GregVandenbussche]

Nice! Thanks Michael ! Maybe I can go as low as 5A then !

[Michael Branning]

Nice! Thanks Michael ! Maybe I can go as low as 5A then !

I think so, but I did not measure any impulse current for turning on lights or switching between hi/lo. I’d try it, but carry some 7.5a fuses just in case.

[James Learmonth]

Greg

Great looking install on the fuse box. As far as the Question of which fuses to use I followed the advise of Joe Leoni
about six years ago that with a 12 volt conversion use 8 Amp fuses for all circuits. For me thats all the white ones.
I haven't had a problem at all.

Jim Learmoth
65C Coupe
Houston, TX

[Martin Benade]

Part of what makes a correct fuse rating is that it be low enough to blow before the wires melt. That is more important than the now lower current draw of the led lamps, although you could run lower amp fuses too.

[GregVandenbussche]

Thanks James & Martin! Will switch all of them to 7.5 tomorrow, i'll keep larger rating handy in the glove box

[Hugo Karasawa]

Greg,
Found this diagram for BT6-C . You should be fine with the 7.5A fuses.
And you can also use Smart Glow fuses by littelfuse, if a fuse blows a led will indicate which one is blown.

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Smart Glow Fuse.jpg (50.88 KiB) Viewed 781 times