"Paul Michael Brown" <
pmb@his.com> wrote in message news:<
pmb-2403021305060001@max3k-69.his.com>...
> THE UNOFFICIAL BMW E31 BUYERS GUIDE
>
> By: Paul Michael Brown
>
E31@his.com
>
> DRIVING IMPRESSIONS & OWNERSHIP THOUGHTS
>
> For those interested in the E31, the most important thing to
> appreciate is that it was designed to be a big, solid, stable grand
> touring car that's optimized for long trips at high speed in great
> comfort. A typical 8-series BMW weighs nearly 4,500 pounds with fuel,
> luggage and a couple of passengers. That's about the same as the
> stodgy Ford Crown Victoria so beloved by senior citizens and police
> departments. So even though the V-12 powerplant delivers about 300 HP
> with torque to match, the power-to-weight ratio is such that the car
> just isn't that fast off the line. Moreover, the control forces are
> quite heavy. This control feel (especially the heavy steering effort)
> is desirable when driving for hours at high speed. But at slower
> speeds and around town the E31 can feel ponderous and truckish.
> Remember, the E31 has a long wheelbase of 2684 mm or 105.6 inches,
> which makes for a rather large turning radius. The body is also long
> (4780 mm or 188 inches) and wide (1855 mm or 74.2 inches) and the car
> had two VERY large doors. So narrow parking spaces and other tight
> spots in the city are going to be a challenge.
>
> If you want a traditional sports coupe in the tradition of the
> legendary //M3, the E31 is not the car for you. The designers made no
> effort to build in sporty handling or "tossability." On the contrary,
> the car is designed to be very stable at autobahn speeds. All in all,
> the E31 is the very antithesis of the nimble, tossable sports car or
> peppy urban runabout.
>
> Another thing about the E31 is that it's easily driven very quickly by
> a driver of average skill. First, you have gobs of torque on tap and
> at anything faster than about 30 mph, the E31 accelerates surprisingly
> quickly, despite its heft. Second, more than 75 percent of E31s are
> fitted with an autobox. If you choose the sport mode, the computer
> locks out the top gear and uses a very aggressive shifting map. So
> forget about matching revs with perfect heel-and-toe technique. Just
> stab and steer and let all that torque, combined with the magic of
> traction control make up for your technique. If you happen to find
> yourself on a road with some longish straight sections in an E31,
> you'll be able to compensate for the time you lose in the twisties. To
> be sure, this isn't exactly a purist's ride. (You'll have to ignore
> the snickering directed at your autobox.) But for the typical driver,
> the E31 is a very forgiving car and quite comfortable to drive
> quickly.
>
> Of course, as I noted above, the ideal element for the E31 is out on
> the freeway chomping up hundreds of miles in a single sitting. In
> this environment, the E31 is simply without peer. From 50 to 100+
> MPH, it's lose-your-license fast. And more importantly, it is
> utterly, totally rock solid and at those speeds. The coefficient of
> drag is a super-low 0.29 and the aerodynamics are such that even at
> very high speeds there is absolutely no lift or even a suggestion of
> skittish handling. (Note how the E31 achieves this without obnoxious
> boy racer bodywork. Proof positive that less is more.) Moreover, out
> on the freeway at speed the E31's bulk and wide track make the car all
> but impervious to crosswinds or dirty air stirred up by large trucks.
> Simply put, the car is devoid of drama and easy to drive fast in
> almost all conditions. I once drove my 1991 850i through the outer
> edge of a hurricane on I-95 in North Carolina. The rain fell in
> sheets and the winds blew with great intensity. But with the cruise
> control set on 70 MPH my E31 ignored the weather. Indeed, the only
> challenge on that trip was finding a gas station that wasn't boarded
> up and closed. In better weather, it's simple to crank off a
> three-hour leg during which you cover 225 miles in a single sitting.
> (Traffic and law enforcement permitting.) I routinely take road trips
> where I drive 650-750 miles in a single day. I get about 19.5 mpg,
> and I arrive refreshed, rested and relaxed. To me, that's the "fast"
> that counts -- not hypothetical hot laps on a track someplace.
>
> With regard to creature comforts, you should know that while the E31
> is in theory a 2+2, the rear seats are useless for anybody larger than
> a child unless your trip is going to be very short. That's just as
> well, because luggage for more than two people won't fit in the trunk,
> which isn't all that large due to the fact that it also holds two
> batteries plus the CD changer and the massive 24-gallon gas tank eats
> up lots of room around the rear axle. So in the end, the E31 is ideal
> for two people going on a road trip. In the front seat the roofline
> is low and the sunroof mechanism intrudes into the headliner a little
> bit. So headroom might be a concern if you are tall or you prefer an
> upright, NASCAR-like driving posture. Most E31 owners, however, find
> it adequate, and the adjustable power seats to be comfortable. The
> stereo was state-of-the-art circa 1990, but by today's standards it's
> no big deal. So don't expect audiophile sound and realize that
> reception on the AM band is going to be poor because the antennas
> (yes, there are more than one) are hidden inside the bodywork.
>
> OK -- if you are still interested in purchasing a used E31 at this
> point, it's time to go to school on the marque. The following should
> prove helpful.
>
> DESIGN OVERVIEW
>
> [At the outset, I would like to express my appreciation to Mr. Mike
> Coenen, who maintains a superb E31 site at
http://www.e31.net. Mr.
> Coenen, prevailed upon Herr Zeichner at BMW's archives in Munich to
> assemble much of the sales and production data that follows.]
>
> The BMW 8-series (internal platform code E31) began production in May
> of 1989 and remained in production until May of 1999. A total of
> 30,581 E31s were built, of which 6,431 were imported into the United States with the
> remainder sold in Europe and worldwide. This discussion will focus on
> the E31 variants imported into the United States.
>
> The first E31 variant sold in the United States was the 850i. It it
> by far the most numerous, representing 4,194 units of the 6,431 E31s
> imported into U.S. (That's just a little bit short of two-thirds.)
> Curiously, data from the BMW archives shows that 647 examples of the
> 850i were sold in the United States during the 1990 model year. But
> frankly, I've never seen a 1990 850i advertised for sale anywhere. If
> anybody owns one, please send me the VIN and I'll look into it.
>
> In 1991 and 1992 BMW sold 2,517 examples of the 850i in the United
> States. MSRP was roughly $75,000. If you are looking to purchase a
> used E31, be advised that the 850I from 1991 and 1992 dominates the
> market, with the 1993 850Ci close behind. The 850Ci from 1994 forward
> is VERY difficult to find. The 840Ci (with the V-8 motor) from 1994
> forward is somewhat easier to find.
>
> POWERPLANT: If you are a true car guy, at least once in your life you
> should own a car with a V-12. And when you look at all the V-12
> powered cars available today, the only one that is even remotely
> affordable is the E31. All examples of the 850i were powered by a 5.0
> liter M70B50 V 12. The M70 engine series features a relatively
> conservative design. For example, there were just two
> hydraulically-adjusted valves per cylinder, operated by a single
> chain-driven overhead camshaft. Compression was a low 8.8 to 1, so
> the engine is not fitted with a knock sensor and it will run on 89
> octane gas. The connecting rods were identical to the nearly
> bulletproof units installed on the legendary 2.5 liter straight-six
> motor fitted to the 525i and other BMW models. Some features of the
> M70B50 engine were slightly more advanced. The 60-degree monoblock
> was cast in an aluminum-silicon alloy BMW called Alusil, and the
> cylinders are linerless. Two sets of engine control electronics are
> installed, one for each cylinder bank. In the event one set fails,
> the car will still operate on the opposite cylinder bank in "limp home
> mode." Think of it as two of BMW's 2.5 liter straight six engines
> sharing a common crankshaft. Power output is roughly 300 HP with 320
> lb/ft of torque. And because it's a V-12, this power is available at
> very low RPM. As the track guys like to say, "horsepower may sell
> cars but torque wins races." So at anything faster than about 30 mph,
> acceleration is brisk and the car feels frisky despite its heft.
>
> There is no mechanical throttle linkage on the E31. Instead, a
> "throttle by wire" system is used. After considering a variety of
> factors, including the position of the gas pedal, the engine
> management electronics operate "DK motors" to control the engine
> speed. The DK motors, however, are a maintenance issue. Eventually,
> they wear out and the engine control software does not like that at
> all. You get fault warnings and the car goes into "limp home" mode.
> Rebuilding DK motors is impractical, so you're looking at about $700
> each (plus labor) to replace them. In my view, an E31 with two new DK
> motors should command a premium of $1,000 to $1,500.
>
> Another problem area is the intake manifold gaskets, which develop
> leaks that manifest themselves as rough cold idle. (Very easy to
> mistake for a bad oxygen sensor, by the way.) Dinan used to sell a
> thicker gasket that solves the problem, but as the E31 ages Dinan will
> probably discontinue this item. An alternative repair is to use a
> liquid sealant and the OEM gaskets. In either case, the repair is
> simple but labor intensive. Anecdotal evidence would suggest that the
> M70B50 motor is less prone to this problem than the M73B54 motor,
> perhaps because it's lower compression. But the data is spotty. Again, a car with this upgrade
> should command a premium. Otherwise, you're looking at a $1,500-2,000
> repair if you get a leak.
>
> The last potential engine-related problem is going to be related to
> the cooling system. The E31 features a physically large engine
> stuffed into a small engine compartment that has limited cooling
> airflow. Moreover, unlike more modern cars the E31 is not fitted with
> an electric fan that runs while the car is parked. Nor does it have
> an oil cooler. (Although it's possible to retrofit one from the
> European parts catalog.) So it's vitally important that the cooling
> system be maintained in perfect working order lest you cook all that
> exotic aluminum alloy. Look for evidence in the service logs that the
> car had a cooling system flush and fill at least every 24 months,
> preferably more often. Ask about hot running problems, especially if
> you live in a warmer climate or you encounter stop-and-go traffic on a
> daily basis. A well-maintained 850i from the 1991 or 1992 model year
> will almost certainly have had the fan clutch and the water pump
> replaced. If the seller cannot prove this has been done, plan on
> spending about $1,500 to replace both these items.
>
> TRANSMISSION: About 75 percent of the examples of the 850i were
> fitted with a four-speed ZF 4-HP/24 EH autobox. This transmission
> does a good job soaking up all that torque and getting two tons of car
> moving. A sport mode can be selected that locks out fourth gear and
> increases the RPM where the shifts occur. A primitive manual mode a la
> Porsche's Steptronic may also be employed. The E31 has so much torque
> that rear wheel slip is always a concern. So it is equipped with the
> ASC + T system, which stands for Automatic Stability Control plus
> Traction. If rear wheel slip is detected through the ABS sensors, the
> ASC + T software will reduce the throttle opening even if the driver
> has his foot on the floor. If a rear wheel continues to slip, the
> software will apply the brake, even though the driver may not be pressing the brake pedal.
>
> When the weather is inclement, the E31 will never be confused with a
> four-wheel-drive SUV. But the ASC + T system really does work and the
> car is quite tractable in the rain and even in light snow. A word of
> caution, however. As I note below, many E31s have been fitted with low
> profile tires that are considerably wider than the 235 mm stock
> rubber. Moreover, the use of ultra high performance tires is common.
> This setup works great in dry conditions. But in my view it makes the
> car less driveable in the rain and snow. If you plan to drive your E31
> daily, you should look for a car with tires closer to the 235 mm stock
> size and you should consider fitting a tire with good all season
> performance, such as the Michelin XGT Z4.
>
> About 25 percent of the 850i production run was fitted with the
> Gertrag 6-speed manual transmissions. The Gertrag gearbox seems fine,
> but anecdotal evidence suggests that the clutch is not up to the task
> of launching such a heavy car with so much torque. So if you find a
> six-speed E31 you can probably expect to replace the clutch more
> frequently than you would on, say, a 328is or even an //M3. In my
> view, the autobox is the better transmission because it's more
> compatible with the Grand Touring design of the E31. When inspecting
> the service logs of a used 850i equipped with an autobox, look to see
> if the owner has replaced the fluid and filter roughly every 12-18
> months. The use of Mobil 1 synthetic ATF is a real plus. If this has
> been neglected, you could be facing expensive autobox maintenance in
> the future.
>
> SUSPENSION: The front suspension features double-jointed struts with
> integral shocks and coil springs, while the rear features a multilink
> setup using separate coil springs and active rear wheel steering. The
> front thrust rod bushings are a wear item. A car with new bushings,
> preferably with new thrust rods and a new idler arm as well, should
> command a premium. The ride is tuned to be comfortable in the GT car
> tradition, not jarring in the sports car manner. The 850i was fitted with
> 16-inch wheels wearing 235/50 tires. The stock BMW wheel was cast
> aluminum alloy in the "basketweave" design, and the optional BMW wheel
> was forged aluminum alloy in the ellipsoidal "turbine" design. IMHO,
> the latter is handsome without being trendy and its easy to keep clean
> of brake dust.
>
> Unfortunately 235/50 x 16 is an "orphan" size tire that's difficult to
> find, so many examples of the E31 will be fitted with 245/50 tires on
> the stock BMW wheels, or you'll see a "plus one conversion" to 17-inch
> aftermarket wheels and lower-profile tires. Occasionally, you'll find
> a "plus two" conversion to 18-inch wheels and super-low-profile tires.
> In my opinion, the stock 16-inch wheels (using 245/50 tires) provide a
> comfortable ride and more grip than you'll ever need. Granted, it
> won't look as cool as a plus one or a plus two. But you won't be
> tramlining or bending rims either. Of course, you may not worship at
> the altar of stock as I do. So YMMV.
>
> ANCILLARY SYSTEMS: The E31 was equipped with every conceivable
> creature comfort and gadget that BMW could think of, including
> voice-activated cell phone, trunk-mounted CD changer, dual-zone
> climate control, multiple radio antennas hidden inside the bodywork,
> onboard first aid kit plus tool kit, and window glass that
> automatically rolls down a few millimeters when you open the door and
> then rolls up again when you close the door. So don't be fooled by
> ads that say "loaded." All E31s are going to be "loaded." Most of
> this stuff is fairly reliable, but there are a few known problems.
>
>
> For example, the power seats are of a very sophisticated design.
> (Note how the seat belts are anchored to the seat itself, vice being
> connected to the B-pillar, which is absent in the E31. So the seat is
> mounted to the floor pan with bolts that look like they came off a
> battleship.) But the cable that adjusts the bottom cushion gets out
> of rig. This can be seen by exercising the seat through its full
> range of motion and watching to see if the bottom cushion adjusts
> unevenly. It if rubs up against the center console, the cable needs
> adjusting. The fix is simple if you know what you're doing and expensive if you don't.
>
> The onboard computer (OBC) has a large display for displaying
> information about average speed, outside temp, gas mileage, etc. Way
> cool for a late 80s design, but the connector on the ribbon cable
> between the computer's processor and the display is poorly designed.
> Moisture and dust creep into the connector and cause intermittent
> "dead" pixels on the display. Expect all used E31s to have this
> problem to some degree. The connector cannot be cleaned or replaced
> separately, so the only fix is to replace the entire assembly,
> processor, connector and display. Figure $300 for part plus labor to
> remove and replace. Verify the sunroof slides AND tilts. Sometimes
> the mechanism gets out of adjustment and one or both functions stops
> working. Expect the stupid coinholder on the driver's door to look like hell. (A COIN HOLDER?!? What were the guys in Bavaria thinking?)
>
> Usually, the only optional equipment you'll find will be the forged
> (vice
> cast) alloy wheels in the "turbine" design and the Electronic Damping
> Control. EDC is a primitive version of what the Formula One people might
> call an "reactive suspension" in that it changes shock valving on the
> fly. Problem is that even when the system is working it doesn't do much
> for handling. And when it breaks, you're looking at more than $1,000 for
> EACH replacement shock. So if you ask me, EDC is not a selling point.
> Look for an E31 without it, or one where the owner has replaced the EDC
> shocks with conventional shocks.
>
> Almost all E31s available on the used car market will have new shocks,
> which brings up another note of caution. Using BMW parts requires
> replacing the entire front struts, at about $600 each, plus about $150
> each for the rear shocks. Adding labor costs at a good independent
> shop in a big city, the total cast for replacing the front struts and
> the rear shocks with genuine BMW parts will be about $2,500.
> Obviously, a car with this repair should command a premium.
>
> Some owners have elected to use Bilstein Sport shocks, rebuilding the
> front strut in the process. This is drastically cheaper because the
> original front struts are recycled instead of being replaced.
> Sometimes, shorter and stiffer springs from H&R, Eibach, etc. are
> fitted at the same time. This creates a problem. Regardless of whether
> the Bilsteins are installed with the stock springs or in combination
> with aftermarket springs, the resulting ride height is MUCH LOWER than
> stock and the amount of suspension travel is MUCH reduced. Add in a
> plus-one or plus two wheel/tire change (with the super-short
> sidewalls) and the result is
> (IMHO) an EXTREMELY harsh ride that's not in keeping with the E31's grand
> touring character. Moreover, the stress that's usually absorbed by the
> stock tires and suspension has to go somewhere (like the shock mounts on
> the subframe). This is not a good thing for a big heavy car over a decade
> old.
>
> I realize that lots of owners like the look of a lowered car with big
> wheels. And I concede that a suspension that feels harsh to me is
> "comfortably firm" to somebody else. But in the end, I take the
> position that the BMW engineers knew what they were doing when they
> elected to use 50 series tires and taller springs with matching
> shocks. Replacement using the BMW parts maintains the supple ride the
> original designers intended, with no sacrifice in handling. Done by a
> competent independent mechanic, this repair is costly which explains
> why so few owners go this route. But IMHO it's the best way to go.
>
> In 1993, the 850Ci was introduced and MSRP crept up in increments,
> finally reach roughly $95,000. In 1993, the 850Ci was largely
> identical to the 850i save for some creature comforts discussed below.
> (In fact, a tiny number of cars in the 1993 model year still had the
> six speed transmission. The following year the six-speed was
> discontinued. So next to the 850CSi, a 1993 six-speed 850Ci is the
> rarest of all E31s.) From 1994 forward, all examples of the 850Ci had
> the 5.4 liter M73B54 V-12 powerplant and the 5-speed ZF "sealed for
> life" (allegedly) autobox. Inside the cabin of the 850Ci, wood
> dashboard trim was added and the seats were covered in a Nappa leather
> that had a more "gathered" look than the tightly-stretched leather
> used on the 850i. You also get a passenger airbag, at the cost of
> losing one of the two gloveboxes fitted on the 850i. The 850Ci
> remained in production until 1999. However, it should be noted that
> no examples of the 850Ci manufactured during the 1998 or 1999 model
> year were imported into the United States. (The handful that were
> built, were largely sold in Europe.) Compared to the 850i, the 850Ci
> did not sell nearly as well in the United States. So it is considerably more rare on the used car market and it commands a premium price.
>
> In 1995, the 840Ci was introduced. It featured the same chassis as
> the 850Ci, but it was powered by a V-8 engine of 4 liters
> displacement. At first the 840Ci lacked some of the creature comforts
> found on the 850Ci such as wood trim and a CD changer in trunk. But by
> the 1997 model year, the cars were largely identical save for the
> engine. In the 1998 model year, the MSRP of an 840Ci was roughly $75K
> and an 850Ci was roughly $95K. As a result, toward the end of the E31
> run the 840Ci outsold the 850Ci by roughly 3-to-1. In the used car
> market, however, you see a paradox. Even though the 840Ci has a
> lesser motor and (on some models) fewer bells and whistles than the
> 850Ci, it generally sells for MORE. In my view, this is because the
> 840s are generally newer and buyers are concerned about maintenance
> costs associated with the V-12, such as the DK motors and the intake
> manifold gaskets. On the other hand, the M60B40 V-8 motors with the
> Nikasil blocks fitted in early examples of the 840Ci react adversely
> to the higher sulphur content in U.S. blend gasoline and the cylinder
> bores are damaged, causing a leakdown problem. In early 1997, BMW
> began making the V-8 blocks from Alusil, just like the V-12 blocks.
> Meanwhile, many of the motors with the Nikasil blocks have been
> replaced by motors with the Alusil blocks under a special rule
> instituted by BMWNA. So if you're looking at a 1994-1996 840Ci, you
> should ascertain what type of block it has and negotiate accordingly.
> For more than you ever wanted to know about this, I invite our
> attention to the superb report by BMW Master Mechanic Brett Anderson,
> at:
>
>
http://www.koalamotorsport.com/v8shortblock.htm.
>
> Of course, no discussion of the E31 would be complete without
> mentioning the mighty 850CSi. Imported into the United States only in
> 1994 and 1995, the 850CSi fetched in excess of $100K when new and it
> featured numerous tuner modifications that resulted in true supercar
> performance. For example, it featured: "variable throttle linkage,"
> by which the gain in the electronics could be varied to make the car
> more tractable around town and more responsive elsewhere; variable rev
> limiter (limit varies depending on what gear you are in 1st and 2nd
> = 6400, 3rd = 6200, 4th = 6100, 5th and 6th = 6000 RPM); Yew hardwood
> trim (and more wood in general than a non-CSi); special lighter
> pistons; longer stroke (from 75 to 80mm); wider stock tires; vehicle
> speed sensitive steering as opposed to engine speed sensitive
> steering; different steering ratio; double-wall larger diameter
> forward exhaust pipes; "BMW Motorsport" door handles; stainless steel
> (not chrome) exhaust pipes; BMW "M" steering wheel; and the tachometer
> has a slanted redline indicating the variable rpm limiting. There were
> also specific color combinations available. Think of it as an //M8
> without the badge. Only about 200 exist in the United States as I
> write this. If you can find one, you'll pay at least $55,000. This
> is the ultimate version of the E31 -- a true exotic. Don't be fooled
> by fake versions of the 850CSi for sale. See below on how to
> recognize the genuine article.
>
> SALES HISTORY
>
> With only 30,000 sold in nine years the E31 was never a smash hit. (Honda
> sells that many Accords in a MONTH.) The E31 was introduced in the
> summer of 1991 during a recession in the United States and it seemed
> like the market for big coupes seemed to dry up right about that time.
> (Which was also about the same time as the SUV craze began to take
> off.) IMHO, the E31 had several problems from a sales standpoint.
> First, it wasn't a traditional BMW. By that I mean it wasn't a nimble
> sport sedan or sport coupe. Rather, it was a big, honking,
> Autobahnstormer. In other words, the kind of car Helmut Kohl would
> love. At triple digit speeds, the E31's bulk and power and solidity
> was an asset. But around town it could be a handful. And it
> definitely didn't fit the average Bimwad's ideal. So the traditional
> BMW owner base virtually ignored the E31 and the tuner/track/autocross
> crowd tended to purchase //M3s.
>
> Second, the E31 is a very maintenance-intensive car. To own an
> 8-series requires a substantial investment in upkeep and a high
> tolerance for downtime. The captains of industry who bought the car
> were generally not willing to accept this. They figured that after
> shelling out in excess of $75,000 for a car, it ought to require only
> the cheapest and most infrequent of upkeep to be totally, utterly,
> superbly reliable. In other words, they wanted a car that was an easy
> to maintain as a Japanese luxury sedan. (E31 Owners Joke: "What's the
> best place to find a used E31? On the used car lot of the local Lexus
> dealer!") Yet they wanted it to drive like a BMW. Not gonna happen.
> So the prices of used E31s have fallen dramatically.
>
> Of course I'm biased, but I think that big coupes are going to make a
> comeback. All those middle-aged rich guys are going to soon realize
> that their Z3 or their Boxster or their S2000 is fun for the
> occasional weekend jaunt. But when it comes to a daily driver or a
> car for longer trips, something more substantial is called for.
> Granted, they could buy a 7-series or an S-Class Benz. But the
> 50-something guy in the four-door German sedan is a cliche. I predict
> drivers with a little more style are going to rediscover the E31.
> IMHO, the styling still looks sharp -- even though it's been a decade
> since it hit the market. And the 8-series is rare enough to turn
> heads. Finally, for the driver who's tired of a stiff sports car
> ride, the E31's handling is a refreshing change.
>
> CONTINUED IN VERSION 2.1, PART 2 OF 2