I sent out a press release and did some blogging for Jonny at Classic Retrofit yesterday, telling the story of a German 911 enthusiast who had gone to the trouble of measuring the improvement in headlight output after fitting one of Jonny’s replacement blade fuse panels.

I just love the story: it is charming and simple and so down to earth. Perfectly suited to Classic Retrofit. Jonny’s clever replacement fuse panels for classic Porsche 911s have proven to be an exceptionally popular upgrade amongst owners who wish to add reliable modern blade fuse technology to their vintage air-cooled Porsches.

 With several hundred of these plug-and-play Porsche fuse boards now in active service beneath factory fuse panel covers, one defining feature of the Classic Retrofit fuse panels is a pair of built-in headlamp relays.

The relays divert current for the infamously dim headlamps away from the column-mounted light switch, supplying the headlamps directly from the battery. Most of us who started in 911s many years ago fitted headlamp relays to improve light output – I have put them on all of my 911s – but Jonny’s boards go a step further, integrating the relays into the fuse panel and making the whole lot fit under the standard fuse panel cover.

Wolfgang’s Porsche 911 3.2 Carrera

Based in Potsdam, in the suburbs of Berlin, Wolfgang Nothnagel is the owner of a special edition US 1989 Carrera 3.2 in superb condition. Wolfgang keeps his car classic and looking as close to stock as possible, so his subtle mods to date include a stainless steel exhaust system, Osram ‘Nightbreaker’ street legal headlamp bulbs in standard light units and all new suspension rubbers underneath. With ‘everything stock’ as the mantra, Jonny’s upgraded blade fuse panels were the perfect low-key upgrade for the standard factory fuse panel.

“With the storm going over Germany, I used the time to finally fit the fuse panel,” said Wolfgang, who runs a lighting design and event staging company in Berlin. “Replacing the fuse board was done without issues in just forty-five minutes. On the incoming side, there was a need to redistribute one or two of the bundled wires, because the opening receptacles of the new fuse board are smaller. Other than that, the changeover was easy.

“To measure the light output, I used a Gossen Mavolux light meter from our workshop. I don’t claim that the measured output is the highest possible peak point, but the spot used for the measurement was more or less in the centre of the beam. Also, the sensor and car were not moved in between the process. So the delta in readings is valid to display the change in light output due to the relay circuit.

“To my surprise, I got a very different readout in between the original wiring style and switching to the new relays. There was an improvement of some 18%: just the right thing to have through the darker autumn and winter evenings. I am very pleased with the results!”

I have some panels to fit to my car and will get around to it eventually, but my favourite part of this story is a: that Wolfgang is such a cool character and b: that 911 people all over the world who run apparently stock examples still love to play with their cars. So much of the original technology in an old 911 has now been superseded, so it makes perfect sense to fit improved technology that doesn’t interfere with the look of the car, but will deliver more effective performance and improve the ownership experience. This is exactly where Jonny comes at all of his products from.

“As Wolfgang pointed out in one of his emails, the original fuse panels in his car worked for twenty-five years without major issue,” says the esteemed Mr Hart, “but upgrading to our fuse panels using the more available blade fuse type with LED blown fuse indicators and additional headlamp relays makes perfect sense. The project is easily DIY-able, our fuse panels for pre-73 and impact bumper 911s are very affordable and everything fits under the original covers.

“Kudos to Wolfgang for measuring the improvements and sharing his findings. It reminds us what we love about our work: so many great people!”