BMW E30 M3 Buying Guide
Fast, focused and rewarding, the E30 M3 is now commanding serious money. We show you how to spend wisely…
How much to pay
• Project £20,000 • Good £40-55,000 • Concours £55,000-150,000 •
• Most expensive at auction: £78,400
Running costs ★★★
DIY Friendly ★★★
Homologation requirements have given us some fabulous cars over the years, and few more so than the BMW E30 M3. It instantly evokes the halcyon days of Group A Touring Car racing, when BMW went toe-to-toe with Ford and Mercedes, and the likes of Roberto Ravaglia and Johnny Cecotto put the M3 on the map.
The blend of exquisite balance from the chassis and race-bred performance from the screaming four-pot makes this one of the most rewarding driver’s cars of all. That, allied to the craze for all things 1980s and performance-related, has meant that values for the M3 have skyrocketed.
Cars that were £20,000 only a few years ago are now twice that, and the best Evo models have long since broken the £100,000 barrier. Still, who can put a price on the ability to make a Sunday-morning run feel like a qualifying session at Monza?
Your AutoClassics BMW M3 inspection checklist
During the M3’s development, the fastest roadgoing E30s were six-cylinder cars, but that layout wasn’t ideal for racing. The ‘four’ that BMW settled on was the M635CSi’s 24-valve twin-cam but with two cylinders removed. It could rev harder than the bigger unit, was lighter and could be better positioned for weight distribution.
It’s a remarkably resilient engine, taking six-figure mileages in its stride as long as it’s well looked after – service history is vital. Valve clearances need to be set with bucket and shim, so it’s not uncommon for those to be incorrect.
The timing chain is one of the key areas. The neoprene guides can get brittle, so listen for a rattle on start-up and at idle. Replacing a tired chain is costly, but not when you compare it to an engine rebuild should it fail. It’s possible to retro-fit the E46’s chain tensioner.
Look for signs of overheating, which can cause head gasket problems, and ensure that the fan cuts in correctly. Also look for oil leaks. A worn oil pump will eventually ruin the engine due to a lack of pressure.
The M3 employs a dogleg Getrag five-speed gearbox that drives the rear wheels via a limited-slip diff. It can be a weak point, so listen for bearing noise (which will disappear when you press the clutch at tickover) and check for weak synchromesh – the shift can feel notchy.
You’ll also need to get underneath and check for signs of leaks, which could suggest worn selector shaft seals. If the differential is rumbling, meanwhile, it probably needs new bearings and seals. The gearbox can be rebuilt easily enough by a specialist, but obviously that’ll come with a four-figure bill.
Suspension and brakes
The best M3s will still feel taut and sharp, but there are plenty out there that have been modified, which is likely to ruin the ride, or are suffering from worn bushes, which will make it feel uncharacteristically soggy.
You’ll need to have a very good look around underneath the car – if the rear subframe has dropped on to its mounting plate, the bushes need to be replaced. There’s a third mount above the differential, too. While you’re under there, have a look at the anti-roll bar links and make sure that the dampers aren’t leaking (the standard model gained Boge electronic dampers in 1989).
Worn tie-rod ends can show up as a judder under braking – which is often mistaken for warped discs – while a squeal from the steering might be a sign of a tired drive belt.
Rust is an M3’s biggest enemy, and it’s worth bearing in mind that only the bonnet and doors are shared with other E30s. The light, stiff shell can be compromised by serious abuse, so you really need to see the car up on a ramp. Look for signs of accident damage and repairs, poorly fitting doors and replacement panels. Missing trim panels and wheelarch liners can be giveaway signs, too.
Check the front wings for corrosion, especially around the indicators and along the lower edges, and then along the jacking points and sills. These are often the first to go, and are hidden beneath plastic covers.
You’ll also need to pay attention to the floorpans and the scuttle, plus the battery box. Also have a look around the front subframe for cracks near the engine mounts, and the lip under the front grille.
The best advice is just to check everywhere, really. A specialist inspection, especially one that enables you to properly look underneath the car, could be money very well spent.
All E30 M3s were left-hand drive when new, although a few have been converted to right-hookers. Interiors are well laid-out and durable, with most cars being fitted with cloth trim – the Sport Evo had a particular style of Recaro that is shared with the Lancia Delta Integrale, but with a different mounting and other detail changes.
Cracked seat frames on all variants are difficult to fix, while the Cecotto and Ravaglia special editions had more luxurious interiors. If the clips that hold everything together fail, it can look scruffy but isn’t the end of the world.
The electrics can suffer from corrosion, which causes no end of problems and is expensive to sort. So, make sure that the service indicator works and that the warning panel shows ‘CHECK’ when you start the engine, and ensure that everything that is electrically operated does what it’s supposed to do.
- 1986: M3 introduced in September.
- 1987: Evo model added – 505 built.
- 1988: Evo II with 220bhp – 501 built. Cabriolet hits showrooms.
- 1989: standard model uprated to 215bhp.
- 1989: Sport Evo launched with 238bhp and bodywork mods.
- 1990: saloon production ends; cabriolet continues into ’91.
As with many performance cars that have had a period of being relatively affordable, the main challenge is now finding an M3 that is well maintained and unmodified. If you do – and it might not be the work of a moment – you’ll be rewarded with a spectacular driving machine that could, if required, be pressed into regular service.
Parts availability is good, as is specialist back-up and community support. It would be well worth picking the brains of those last two before you buy as well as afterwards, because there are a number of areas that could trip you up.
Don’t let high mileage put you off, and go on condition rather than spec. You’re better off with a well-maintained standard car that’s been regularly used than you would be with, for example, a low-mileage Sport Evo that’s had long periods of neglect. Whichever variant you plump for, a good one will pay you back in spades.
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Description: - Matching numbers- Full restored in 2012- Extensive restoration file- 1600 miles since restoration- Good running order- 12v electrics and electronic ignition- Rare USA made panniersRegistration No:BDV581B Frame No:639233Engine No:639233CC:493 MOT:April 2018
Description: - Matching numbers- UK registered from new- Buff log book and V5- New special order with L/H sidecar fittings for 1st owner Brakewell & Green- 1952 Steib 501- Mostly unrestored and original- Good running orderRegistration No:358 KAU Frame No:620992Engine No:620992CC:600 MOT:Exempt