It’s been a great year for my friend and fellow impact bumper 911 owner, Jonny Hart, who runs UK classic car electronics company, Classic Retrofit. Having released his replacement Porsche 911 blade fuse panels last year to a highly receptive audience, 2016 saw the launch of Jonny’s CDI+ unit, which replaces the ageing Bosch CDI ignition box, bringing modern electronics to the air-cooled 911 in a plug-and-play upgrade that has been dyno proven to increase power and torque.

Classic Retrofit has now sold almost one hundred of these CDI+ units, and hundreds more of its replacement fuse panels are also in use, clocking up tens of thousands of reliable miles in classic 911s all over the world. Jonny is celebrating the success of his creations by offering the CDI+ box and the appropriate replacement fuse panels for air-cooled Porsche 911s at a discounted price of £995, saving £100 off the cost of buying the items separately.

Classic Porsche 911 Upgrades

We hear a lot about various upgrades for classic Porsches, but few really impress once you start clocking up the miles. For example, there are plenty of suspension upgrades out there nowadays, but not many that work without compromising on cabin noise and ride quality. Same for shifter upgrades: only the WEVO shifter has ever felt like a quantum leap forward on early cars to me.

Jonny’s parts are developed to a similar level. The replacement fuse panels bring modern blade fuses and blown-fuse LED indicators to the seriously outdated ceramic fuse panels which cause so many problems on old 911s. Ceramic fuses are no longer available: these fuses are now plastic. The old fuse panel connectors are riveted together and that connection degrades over time, increasing resistance and heat. The heat melts the plastic and the fuse shortens, intermittently interrupting the connection and driving you mad trying to fix it.

All of my impact bumper cars have had this problem and Jonny’s fuse panel cures it completely. It also adds upgraded headlamp relays for brighter lights, with current running away from the switch a much safer option. The panels are a total no-brainer: a must-fit on all 911s. I have a pair of fuse panels ready to go on my car once I get my alternator back from rebuild and finish converting the electrics to run without a separate regulator.

Bosch CDI Modern Electronics Upgrade

As for the CDI+ units, one of these boxes has just completed a six-week, 10,000-mile trip across the USA on the Pan-American Friendship Rally. Tuthill Porsche has used trouble-free CDI+ units in a number of new car builds, and Neil Bainbridge at BS Motorsport has also used them on a number of cars to great effect. They are super reliable and a simple plug-and-play fitment using the original connectors.

I only run older cars and reliability is non-negotiable for me. Every year, I spend a small fortune repacing parts and future-proofing reliability on my fleet of old classics. Having suffered breakdowns at the hands of burnt-out Bosch CDI units and disintegrating fuse panels, I can’t recommend these parts highly enough. I’m delighted to support this bona-fide air-cooled enthusiast via my impactbumpers.com Porsche forum and also here on the Ferdinand blog. We’re also working on some other projects together: all quite (very) exciting, but more on that later.

See full details of the Ultimate Upgrade Package for Porsche 911 on the Classic Retrofit website.