E31 Eight Series


The E31 was supposedly the replacement for the six series, a car which had been in production from 1976 to 1989! The truth is that it was for a very different market. The 850i was at least 50% more expensive, had a 5.0 V12 M70 instead of the 3.5 inline six used by its predecessor and weighed almost two tonnes.A two door E34 five series should have replaced the six but I've never heard of any plans for one, shame.

So what was the eight all about? Well in 1989 Mercedes bought out a 500SL which was a radical upgrade from the older model, the 850i was BMW's challenger in the top end of the luxury coupe market. And it was a good car when viewed in that regard. Problem was that it wasn't what traditional BMW buyers wanted. Most six owners couldn't afford an 850i or it's fuel bills and I know of many who opted for a 535i instead.

BMW tried to make the eight cheaper by using the new all alloy V8 M60 but this never resulted in huge sales. The eight was never a hit in the market and is quite a rare sight on the roads.

BMW E31 850i

Definitely made for the Autobahn.


The 850i was introduced in 1990 and was phased out in 1998 or 1999 depending on your country. The 840 was born in 1992 and made until 1999. There is no confirmed replacement for the eight although BMW look very likely to build a new V8 based six in a few years.

The eight was the first BMW to have the Z axle rear suspension, Multi-Information Display (MID), traction control, dynamic stability control, electrically adjustable shock absorbers and a raft of other goodies.

The 850CSi was the top of the range. It had a 5.6 V12 S70 which the Motorsport department had breathed on.

Most eights were automatics but a six speed manual option isn't that hard to find. There were several sport packages available with bigger wheels and stiffer suspension. Despite many rumours a convertible never appeared.

My choice would be a 4.4 V8.

BMW E31 Alpina B12

Spectacular Alpina B12 Coupe.


The E31 was introduced with the 5.0 V12 from the E32 750i. There was never an M8 but the 850CSi had an S70 engine which had ties to the Motorsport department. There was a four valve version of the S70, it's in the McLaren F1!

In 1992 the 4.0 V8 was introduced, this had less power but weighed a lot less too. The 4.4 which replaced it had the same power output but more torque.

It's a shame the new M5's engine came too late for the 840. An E31 with a 400bhp V8 would have been a great car. See the engine details page for power figures.

Model Body styles Engine Weight
Power / Weight
(bhp / 1000kg)
Final drive ratio
(manual / auto)
840i (early 4.0) Coupe M60 1895 151 2.81 auto Disc/Disc ABS
840Ci (late 4.4) Coupe M62 1895 151 2.93 auto Disc/Disc ABS
850i / Ci Coupe M70 1960 153 2.65 US / 2.93 manual / 3.15 auto Disc/Disc ABS
850CSi (5.6) Coupe S70 1925 198 2.93 Disc/Disc ABS


The graceful lines of the 850i.

Known Problems

For the 840i M60 engine problems.

For the 850i see M70 engine problems.

For the 850CSi see S70 engine problems.

I've heard surprisingly high numbers of complaints about build quality on early models. Many dealers seem unfamiliar with these cars.

The E31 was the test platform for many new electronic systems such as DSC which later spread to other BMWs. Make sure everything electrical works.

Full service history is vital if buying an E31. Eights depreciate very heavily and can make a good used buy after a few years.

BMW E31 eight series Hartge

An 8 with Hartge wheels.