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uwbuurman wrote:was die nieuw of nog de oude as, Arnold?

I have been lurking after E39 530i Touring’s recently to replace our current daily (MB W203). In that process, I found a nice example (on paper) on mobile, but its location in the far east of Germany just a few kilometers shy from the border with Poland meant a nice continental trip had to be made to examine it.

considerations
Normally, I would avoid to use #231 for such demanding trips; I consider the E28S as a luxury that needs to be used appropriately. But due to the current high-pressure zone over the continent, the ambient temperatures hover around the 25°C mark with very low humidity; making ideal driving conditions for #231 to add up some miles on some unrestricted German autobahns.

route
The distance to Trebendorf according to the Michelin route-guide is little more than 660km, most of which on the highways, consecutively the A1 (A30), A2, A10, A13, A15. As I was early, there was hardly any traffic on the four lane A30 from the Dutch border towards Bad Oeynhausen. The following A2 towards Hannover and Potsdam has been extended fully into a six lane highway, the cruising speed ranged between 160km/h and 230km/h on the speedometer only reducing speed for slower traffic. Traffic would easily allow more, especially between Hannover and Magdeburg, but this would be contra-productive as more refueling-stops would be needed.

Engine
The engine runs smooth and is flexible; the rebuild engine pulls already pulls strong and linear from the low-range in the highest gear up until very high speeds. The engine doesn’t feel that fast, but that is misleading; I was repeatedly surprised after I looked at the speedometer. When accelerating from 100-120km/h (most of the time in fifth gear), the speedometer indicated more than 180km/h when I expected no more than 160km/h. Granted, 286hp was impressive twenty five years ago and now there are heaps of cars producing output in that range, but there will be very few that are capable of doing so in the same way. It delivers its power effortlessly and smoothly without hiding its racing origin.

For example, I was really impressed with the ease of maintain high speed on the highway between Bad Oeynhausen towards Stadthagen in Germany. As some of you may know, this section is located in a mid-sized mountain range (Porta Westfalica). The typical incline is between four and five percent. Combined with the road-layout, this is a serious challenge for any car and driver. From time to time, I had to reduce speed to about 120km/ for slower traffic. After the road cleared, the flexibility of the engine allowed me to quickly accelerate to my cruising speed of about 180km/h without even stressing the engine (no WOT usage). This is something that an E34 M5 simply is not capable of without selecting a lower (fourth) gear.

Results of throttle body synchronization
I just managed to complete the basic mechanical throttle body synchronization the day before. The first impressions in around town looked promising. Idle is smooth and stable and the transition from ‘no-load’ to ‘part-load’ is smooth and swift. The slight shock that could be felt prior to the engine management transiting from ‘load’ to ‘no-load’ when lifting throttle disappeared completely. With other words, a significant improvement compared to the previous attempt (July 2011).

During the throttle body synchronization, the Throttle Position Sensor’s WOT switch engaged about five degrees before reaching the maximum opening of the butterfly valves, allowing for some margin against operation at Wide Open Throttle (WOT). However, most of the acceleration was done with the throttle-pedal depressed at no more than 70%. On some occasions though engine was deliberately operated at WOT to test the transition from ‘part-load’ to ‘full load’, which also is fluent.

Since the synchronization of the three push-roads in ‘idle’ is done with 0,01mm accuracy, it is impossible to compensate for the tolerances in the butterfly system mechanically. That is only possible by synchronizing the intake-vacuum of the six intake ports, something that can now be scheduled.

Fuel consumption
Throughout the day, I had to refuel four times (!). Generally, I prefer to buy the highest octane rating as possible, but I had to settle for Total Excellium 98 on one occasion between Magdeburg and Potsdam. Although Total’s premium products octane rating meets the M88/3 requirements, I rate it as crap compared to for instance Shell’s V-Power Racing (100RON) or BP (Aral) Ultimate (102RON). Generally, I’d say that the higher the octane rating the better the M88/3 runs and reacts to throttle commands.

In average, #231 needed between 12-13ltrs/100km (21,8-23,6mpg), which IMHO is very acceptable on a high speed long distance continental trip like this.

Conclusion
This was the first cross-continental trip with #231 since the engine rebuild and she didn’t disappoint. In fact, I am very happy with her now I have had an opportunity to stretch her legs and get a good idea about her long-distance travelling capabilities. The recent throttle-body synchronization has been a success and thus an important milestone in the re-commissioning phase has been reached, allowing to proceed with the next step, adjusting the intake vacuum.

uwbuurman wrote:dat zijn best handige apparaten, vriend van me heeft er ook 1. Voor echt lekker werken met hoogte is deze niet handig, maar net wat je zegt, bij beperkte hoogte is het echt heel erg handig! En het werkt al met een gewone compressor.

uwbuurman wrote:vandaag de restauratie van de e21 weer wat naar achter geschoven. Ik had de offerte binnen voor het vervangen van het roetfilter en de koppeling van de e91 binnen. Das samen toch weer ff 2600 euro, exclusief vliegwiel, waarvan ik denk dat deze toch mee moet. Daarnaast moet er een grote beurt utgevoerd worden en ik denk dat de luchtmassameter aan het doodgaan is. Schat het hele zooitje op ergens tussen € 3.500 en € 4.000 onderhoud...