Description
BMW Alpina B3S Convertible (E46), 2004 — Techno Violet with Silver Grey piped leather interior and rare Birch wood anthracite trim.
This is a genuine, factory-built Alpina B3S Convertible — naturally aspirated straight-six power delivered with the composure and refinement Alpina became known for. Full, documented service history from new, with four owners and long-term enthusiast care throughout its life.
COMPLETE ALPINA BOOKPACK & ULEZ CERTIFICATE
DRIVING EXPERIENCE
The B3S is noticeably smoother and more refined than a standard M3 Convertible. Suspension tuning feels far better suited to UK roads — composed over poor surfaces, yet still planted and confidence-inspiring at motorway speeds. It's as much a grand tourer as a performance car: roof down, long journeys are genuinely relaxed and comfortable — the sort of car you could happily drive to the South of France in comfort, with serious pace and presence whenever you want it.
FULL SERVICE HISTORY & BEYOND - FOLDER FULL OF INVOICES & PAPERWORK
Initially by BMW main dealer, then consistently by respected independent BMW specialists:
03/ 11/ 2004 – PDI – Alpina/ BMW – Pre-delivery inspection
10/ 05/ 2007 – 14, 347 miles – Westerly Exeter (BMW) – Oil service
01/ 10/ 2010 – 26, 083 miles – Westerly Exeter (BMW) – Oil service + inspection, rear drop links and bushes replaced
26/ 06/ 2012 – 32, 214 miles – DARMECH – Oil service + major
02/ 07/ 2014 – 38, 091 miles – DARMECH – Oil service
23/ 06/ 2016 – 42, 355 miles – Devon Independent BMW Specialist – Oil service + inspection
01/ 02/ 2018 – 47, 072 miles – CPC Performance Engineering – Oil service + inspection + major, drivetrain service (gearbox + differential), sump gasket
09/ 08/ 2019 – 51, 046 miles – DM Works – Oil service, coolant flush, OEM BMW brakes and discs all round
25/ 09/ 2020 – 55, 251 miles – CPC Performance Engineering – Oil service, brakes rebuilt (new pistons and rubber seals), Alpina OEM suspension replaced with new OEM BMW components (top mounts, rubber guides, collars etc)
18/ 08/ 2022 – 59, 975 miles – CPC Performance Engineering – Oil service + inspection + major, belts replaced
29/ 07/ 2024 – 66, 171 miles – CPC Performance Engineering – Oil service, alternator professionally refurbished (original Valeo unit retained)
18/ 06/ 2026 – 69, 572 miles – CPC Performance Engineering – Major service: engine oil and filter, differential oil.
Michelin Pilot Sport 4 tyres fitted all round — a match for the car's character and what would have been supplied from factory.
MAINTENANCE PHILOSOPHY
Work has always been preventative rather than reactive — gearbox and drivetrain attended to oil changes, a full suspension refresh using Alpina OEM parts (now no longer available new), brake calipers properly rebuilt, OEM pads and discs and a clean MOT history. Correct parts have always been used where it matters — for example NGK specified spark plugs with the correct part numbers, rather than generic equivalents.
CARE & DETAILING
The convertible roof has been treated with Auto Finesse Canvas Protector to preserve condition and water resistance, and operates exactly as it should — up, down, and everything in between. The car also comes fitted with the genuine Alpina-etched wind deflector, a lovely detail that also happens to be genuinely expensive to source aftermarket. The paintwork has had an annual full correction using Menzerna compounds as a proper two-stage machine polish, with a full annual detailing cycle: wheels off for a deep clean, snow foam pre-wash, two-bucket safe wash, clay bar decontamination, and two-stage machine polish. All rubber seals treated with Gummi Pflege to maintain condition.
CONDITION
The paintwork is in very healthy condition for its age and presents exceptionally well, but this is not a concours, flawless example. There are some minor age-related marks and a small number of previously repaired scratches. Localised paintwork has been carried out over time, including on the bumpers and sills, to address stone chips and wear consistent with genuine use. The approach has always been to maintain and improve rather than let anything deteriorate, and the car retains strong depth of colour and gloss.
AUDIO & INFOTAINMENT
The car has been fitted with a genuine Alpine ILX-705E46, a model designed specifically for E46 fitment by Alpine, one of the best names in car audio — not a cheap generic Android It's a plug-and-play installation with no wires cut, so it's fully reversible. It integrates with the factory steering wheel controls and brings the cabin nicely up to date without compromising the car's originality. The original BMW CD changer, head unit and speakers are all supplied with the sale, should a future owner wish to revert back to the original setup.
The original front speakers had reached the end of life and have been replaced with Infinity units and a crossover, giving a noticeably better front soundstage. As a bit of an audio enthusiast myself, I deliberately kept this a subtle setup. I've been chasing an Alpina for years. After experiencing what a B10 V8s ould do — composed, effortless, devastatingly fast in a completely different way to a typical M car, planted and limitless at speed — the itch never really left me. I came close in 2014 to an immaculate 2004 E46 B3S, but lost out at the last moment to a dealer who outbid me. Life moved on, but the search never really stopped — constant trawling of Autotrader, eBay, and the Alpina Register forums, always looking for the right car.
Eventually a fellow Alpina Register member sent over a link to a sparsely written eBay advert — the kind most people would scroll straight past. Something about it felt right.
The seller was a 76-year-old proper petrolhead — bikes, Porsches, and this Alpina, all spoken about with equal passion. This wasn't just ownership, it was stewardship: he and his wife had shared the car for 13 years between them as owners 3 and 4. Going through the history folder later filled in more of the story — a letter tucked among the invoices from the second owner, a businesswoman from the Midlands, who'd moved on to a Boxster but made clear she loved the car. The first owner, almost certainly Midlands-based too, had specced and ordered the car new through Sytner Solihull — the original registration gives that away.
The plate on the car now is a personal touch — a shorter set of characters that I felt suited the lines better, with the original age-identifying plate retained with the car. They were finished with BMW and Alpina emblems along the bottom — a small detail, but one that adds to the patina.
For the last 9 years the car has been in my hands, maintained as a long-term keeper rather than a short-term asset, and enjoyed at Alpina and BMW community events over the years.
THE SOUND
One of my favourite things about this car is the exhaust note. It's naturally aspirated, tuned in the true Burkard Bovensiepen spirit — bassy, with a proper straight-six rasp rather than an aggressive scream. I've also experienced the S54 in a previous car of mine, which is a genuinely amazing engine but much more of a screamer by comparison. The B3S still sings as the revs climb, just with more subtlety and grace. A lot of that character builds through the cam VANOS, and the kickdown on my car is lovely and sharp, exactly as it should be. The Alpina switch-tronic paddle buttons on the wheel — a real Alpina signature — work effortlessly too, should the occasion ever call for it.
My favourite thing about it has always been the way it drives — effortless, composed, and capable of covering serious distance in real comfort, roof down, without ever feeling like hard work. It's a car that rewards you every time you take it out, and it's always drawn attention and compliments wherever it's been.
I'll be back in Alpina ownership again at some point — this is a pause, not a goodbye — but for now it's time for someone else to enjoy it as much as I have.
