Looking Back At The BMW Roadster, Part 2

[JoshCalkins]

1991 BMW Z1

On Wednesday we took a look at the history of Classic BMW roadsters, from the 3/15 DA-3, which premiered in 1930, to the 507, which ended its production run in 1959 (check it out here). After the 507 was discontinued, BMW was on financially-shaky ground, and would spend the next several years cementing its reputation as a quality car manufacturer. In 1989, thirty years after the 507's demise, BMW made a return to the roadster market with the Z1.


The "Z" in Z1 stands for "zukunft," which means "future" in German. While the Z1 may have been envisioned as a new and boundary pushing model for BMW, it was based on an already proven BMW platform: the E30. There were some changes made to the E30 design, however. While the engine, transmission, and front suspension made the transition virtually untouched, many other parts of the vehicle were either modified or replaced. Most obvious to the naked eye is the door mechanism utilized in the Z1. Rather than having a door mounted on hinges that would swing front, back, or up, BMW designers came up with a drop-down door that would recede into the sill. The Z1 could be driven with the door raised or lowered, and for this reason it is considered unsafe, and hence illegal, in the United States.

1990BMW Z1

The Z1 exhibited other notable advancements for BMW designers. For example, the Z1 was perhaps the first BMW vehicle designed using a rigid adherence to aerodynamics. The bottom of the car was covered with a flat undertray designed to reduce drag, and even the mufflers were shaped with an eye towards providing downward aerodynamic pressure on the rear of the car in order to increase traction. A testament to this design is that the Z1 had a drag coefficient of 0.36 with the top up. The modern Z4 has a drag coefficient of 0.34 and the benefit of another 20 years of automotive design technology. Also, the Z1 acheived that drag rating despite that fact that it was constructed of completely interchangable body panels. Within the space of an hour, a Z1 owner could completely remove and replace every body panel on the car.


While the Z1 was a technical marvel, it didn't fair so well in the market. As was often the story for BMW roadsters, the Z1 was initially heralded as a great new roadster and many people couldn't wait to get their hands on one. However, production problems and the complexity of the vehicle limited BMW to only producing about 15 of the cars per day, raising the per capita production costs. These costs were eventually passed on to the consumer and demand began to fall. Certainly not helping the situation was the fact that Mercedes-Benz released a new generation of their SL coupe and convertible that which had a bigger and more powerful engine than the Z1. The Z1 was discontinued in June of 1991, with only 8,000 being made (some sources claim 8,012 were produced).

BMW Z3

In 1996, the Z3 was released, and just like the Z1, it was based off of the same platform that supported the contemporary 3-Series vehicles. The E36 Z3 acheived great success in the auto markets, but this success wasn't completely due to the quality of the vehicle. BMW is credited with running one of the most sophisticated promotional programs of the time when introducing the Z3, supported largely by the vehicles appearance in the James Bond movie GoldenEye. Exposure from that movie, as well as a handful of special James Bond Edition Z3s trageted directly at the most wealthy drivers, caused a demand for the Z3 that did not evaporate. The Z3 was eventually retired in 2002 to make way for the Z4.

BMW Z8

1957 BMW 507 Roadster

A year after the Z3 had first premiered, a BMW concept model called the Z07 was displayed at Tokyo Auto Show. The concept was not initally meant to go into production, and was instead an exercise meant to display how the classic 507 roadster's design could be incorporated into modern BMW models. The concept proved to be so appealing and caused such a sensation that BMW decided to put it into production, renaming it the Z8. Just like the 507, the Z8 was powered by a V8, but unlike the 507, the Z8 had a successful production run. BMW initally planned the Z8 as a limited run model and only produced 5,703 of them. While some complained that the car handled horribly and that the aerodynamics of the vehicle caused excessive wind noise in the cabin, regardless of whether or not the otp was up, the Z8 as a whole was a reincarnation of the classic BMW roadster that had been missing since 1959.

2009 BMW Z4

The Z4 is the current BMW roadster, and the new generation model, premiering this year, is set to be more impressive than the previous generations. While the first generation Z4 was available in both convertible and coupe versions, the new model will only be offered as a hard-top convertible. The previous generation of Z4 produced good sales figures and proved to be a popular model in the company's lineup, and they are expecting the newest Z4 to continue that tradition.


Also, there may just be a new Z model in the offing. Speaking at the Geneva Motor Show this week, lead BMW designer Adrian van Hooydonk, who took over for Chris Bangle, confirmed the existence of the Z10 ED. The model is currently in concept stages and there are currently no plans to show it to the public, but van Hooydonk noted that it would be powered by an inline six-cylinder engine that had been tuned using BMW's EfficientDynamics technology (hence the ED in the model name). The goal is to produce a 400 bhp supercar that doesn't guzzle too much gas. BMW hopes for a 15% increase in fuel efficiency by implementing new technologies. If the Z10 ever makes it into production, it will likely be billed as a competitor against the Audi R8.


In contrast to its shaky start, the BMW roadster is going strong and is gaining in popularity every year. The Z4 likely won't see any redesigns or replacement for another few years, and the Z10 ED probably won't even be displayed as a concept for another year or two, so that's the history of BMW roadsters thus far.

[RadioRon]

Good article. But I cannot let it go without commenting on the undeserved negative spin in the phrase "While some complained that the car handled horribly..." in describing the Z8. This echoes the fact that the British motoring press did not fall in love with the car like many American reviewers did, and in particular shows the influence of Jeremy Clarkson specifically. But "horribly" is an extreme opinion to repeat and is neither balanced by the counterpoint of so many other reviewers who exclaimed the car's virtues both on and off the track, nor is it anywhere near accurate in my opinion.

Having tracked the car and driven it enthusiastically on the street for many years, I agree that the car's handling in stock form falls a bit short of ideal. The car transitioned from understeer to oversteer a bit abruptly when cornering right on the edge, but this is manageable with some skill. I also agree that the car feels a bit heavier than I like for track driving (it weighs about 3500 lbs, which is also why I prefer my E30 318 on the track). I would call these track manners "a bit tricky" but not nearly as dramatic as Mr. Clarkson claims. One comes nowhere near these issues on the street, away from racing limits, and so the huge amount of grip tends to dominate and the car feels wonderful. Anyone serious about turning the Z8 into a supreme track beast can tweak the handling to perfection with a few bolt-on mods. The most effective have been anti-sway bars and different tires. Also useful is installation of a limited slip differential. Yes, the Z8 was not equipped with an LSD from the factory which was rather dumb. I'm sure this contributed to Mr. Clarkson's difficulty in performing those mad power slides with the Z8 as he likes to do.

So, it doesn't seem fair to say that some called the handling horrible without also pointing out that "some" were trying to entertain, not teach.

[JoshCalkins]

Originally Posted by RadioRon Good article. But I cannot let it go without commenting on the undeserved negative spin in the phrase "While some complained that the car handled horribly..." in describing the Z8. This echoes the fact that the British motoring press did not fall in love with the car like many American reviewers did, and in particular shows the influence of Jeremy Clarkson specifically. But "horribly" is an extreme opinion to repeat and is neither balanced by the counterpoint of so many other reviewers who exclaimed the car's virtues both on and off the track, nor is it anywhere near accurate in my opinion. ... So, it doesn't seem fair to say that some called the handling horrible without also pointing out that "some" were trying to entertain, not teach.

It is most definitely true that Jeremy Clarkson likes to blow things out of proportion, and having read some of his reviews and seen him on television, I was aware of this tendency, so I checked with other reviewers. Most were generally positive, but I found a few that echoed his concerns:

Barry Winfield of Car and Driver: "The feel of the car at speed doesn't impart immense confidence, so you're not encouraged to let it really hang out." To be fair about this quote, his fellow reviewer in the same feature, Peter Robinson, did call the Z8, "easier to drive quickly immediately than a Ferrari."

Neil Dunlop of Edmunds remarked on how the Z8 was prone to oversteer and understeer when using the DSC (sorry, I only have my notes on that one, I can't find the exact quote).

Unfortunately, I've never had the opportunity to drive a Z8 so I'm at the mercy of reviewers when determining some of its qualities, but if I find a review of a car and then find two other independent sources that support that review, there is usually a fair amount of truth to it. In retrospect, though, "horrible" may have been a bit strong.

What about the cabin noise? Is it pretty loud? That complaint seemed a bit more universal than the handling criticism. Looking at the car, one can tell that it was designed to echo the 507 and not necessarily be the smoothest vehicle in a wind tunnel.

-Josh

[RadioRon]

Hi Josh
Thanks for responding. Yes indeed the wind that comes into the cabin is very similar to what I used to suffer in my 68 Spitfire and I suspect is very much like many cars of that era, with more upright windshields. So, the reviewers were on the money in general on that issue. How one responds to the buffeting will vary all over the map depending on the age and experience of the driver. In my case, I have experience with older convertible cars and the Z8 is no worse than any of them with the top down so I have chosen to find it charming and move on. On long highway trips, I have found that earplugs are a great benefit to keep from having the lower frequency buffeting tiring you out.

So, while the noise with the top down is part of the retro experience and is easy to accept and ignore, the noise with the soft top up is less easy to excuse. While it only crosses the threshold of unacceptability at high freeway speeds and up, I haven't heard this kind of noise in other convertibles, even old ones. If one tends to cruise at stupidly illegal speeds a lot, then this will be a real irritant. For me, it seldom comes to my attention as I focus my enthusiasm much more on "twisty dancing" than out and out speed.

It bears mentioning that Z8 owners also have the choice of putting the hardtop on the car, which is not difficult, in which case the car is sublimely free of wind noise, all the better to hear the music of the exhaust. The hardtop has no noise issues at all, and it looks wonderful. I've taken my car to a summertime show&shine with the hardtop on just to show it off that way as many people have never seen this configuration.

On the handling issue, I had another read through my old collection of reviews and find that several of the authors had something guardedly negative to say about the car’s handling at the limit as you point out. I also note that these comments are often in contrast to other supercars of the day, including F360 Modena, Diablo GT, 911 Turbo, Corvette Z06, 550 Maranello and many others. This is heady company for a car that aspires to be more of a high performance touring roadster than an out-and-out track animal (the weight is what convinced me of this). So it is no wonder that some of them have something negative to say, since they are, either directly or subconsciously, comparing the Z8 to the very best.


Ron

[JoshCalkins]

Hi Ron,

Your final paragraph about the F360, Diablo, etc. sparked a memory. If I'm not mistaken, one key argument in Clarkson's negative review of the Z8 was that he said the car didn't know what it was, a roadster or a supercar. I suppose that if I were to do a few laps in a Diablo and then switch to a Z8, I may be a little disappointed as well. We should create a new "super roadster" car class so the Z8 can be properly placed.

Also, I can't wait for BMW to release the Z10 ED. It will be interesting to see how they take the Z heritage and give it a complete supercar treatment. Then again, they could also just put their M1 Hommage concept into production and quiet everybody down immediately. And I've just noticed that the picture gallery here doesn't have any photos of the M1 concept I can link to, so I'm off to put some up.

-Josh

***M1 Hommage Concept Photos now in Concepts Gallery here.

[RadioRon]

Clarkson's attempt at making a pair of pants was funny, I admit. Curiously, we discuss his review on Top Gear the TV show as if he was reviewing the Z8 when in fact he was not, exactly. On the show he reviewed the Alpina Roadster V8 (officially, Alpina did not call it a Z8), a car that uses the Z8 body, chassis and interior, but replaces the guts with different engine, transmission (auto), tires, wheels, springs, shocks and some cosmetic bits and bobs to deliver a softer driving experience than the Z8, more suited to the street. Having made that point though, Jeremy did discuss the original Z8 in his introduction to the review. He had reviewed the Z8 in a print article previously and mentioned on the show that he was hard pressed to tell the two cars apart, handling-wise. So, we might as well treat his comments as applying to both, I guess.

I like the M1 hommage styling very much. I don't think the press is prepared to let BMW into the supercar club though. The BMW image is primarily sporting sedans, not supercars, and they're a jealous lot guarding the gates to superdom.

[motoyen]

Did BMW ever address the structural integrity of the strut towers problem some owners were having? I remember reading that some owners had noticed that their body panels were not aligned properly and they thought the cause was the aluminum strut towers being too weak.

[RadioRon]

Originally Posted by motoyen Did BMW ever address the structural integrity of the strut towers problem some owners were having? I remember reading that some owners had noticed that their body panels were not aligned properly and they thought the cause was the aluminum strut towers being too weak.

This issue turned out to be a non-issue but took an interesting twist. It first came to light at the Z8 Club in Germany and got some emotional discussions going on the internet. That club took the issue to BMW and at the same time began a detailed investigation that took about 10 months to complete. The result of the investigation, which was comprehensive, was that the Z8 was no weaker than any other BMW as far as shock strut towers are concerned. They found that cars that had actually suffered strut tower damage had all been in accidents that would have damaged the towers in any car.

However, all of us Z8 owners became aware through this exercise that any frame repairs to the Z8 would cost a lot more compared to a car with a steel chassis. Domed strut towers in a Z8 cannot be pressed back flat because they are aluminum. A correct repair involves welding new chassis pieces to the front of the car, which means disassembling everything forward of the firewall, doing some tricky Aluminum welding at one of two certified BMW aluminum frame/body shops in North America, and then putting it all back together. Holy cow. The costs of such a thing can be enormous.

The Z8 Club in Germany has tight connections inside BMW AG and somehow BMW was convinced to do something about helping members even though the company was adamant that there is nothing wrong with the car. So BMW came out with a reinforcement kit that they called a "Performance Package". This kit applies reinforcing plates at the top of the shock mounts, and adds a strut brace across the engine compartment. In the meantime, owners theorized that an additional improvement would be to get rid of the very hard run-flat tires that came stock on the car.

Facing the small possibility of a really big repair bill for a minor accident, I decided, as many owners did, to install the Performance Package for peace-of-mind. I also happily dumped those crappy run-flat tires in favor of some really good Michelins.

So, yes, BMW did address the perception that there was a problem, but there never was an actual weakness in the car. And as far as the body panels go, yes, there was a few cars that had doming and frame distortion due to accidents and these had some excessive panel misalignment.