I have already written about my experiences of summer testing in North Africa a few times on the MANN+HUMMEL blog. On these trips we repeatedly encountered difficulties with our travel arrangements. When it came to organising the summer engine testing for one of our major clients in the summer of 1976, we therefore discussed in some depth whether a return to southern Tunisia or Algeria was the best option. We decided to look for an alternative destination that offered similarly high temperatures but that was easier to get to.

In spring 1978, we decided to hold the next passenger car engine tests in the US, in Phoenix Arizona. The first test was scheduled to start on 5/6 July 1978. Nonetheless, we soon discovered that the grass is not always greener on the other side, starting with the long flights to Phoenix including stopovers and connecting flights with different airlines. On top of that there was the significant eight-hour time difference. However, we had made our decision so we had to make the most of it.

At that time of year, temperatures in Phoenix were over 40 degrees Celsius! I took a deep breath of cool air in the air-conditioned hall before heading out to start the first test in the oppressive 44 degree desert heat. My first thought was: How are we going to keep this up for two weeks? Luckily we had salt tablets with us; otherwise I think circulation problems would have been unavoidable.

Nonetheless, Phoenix did offer a number of advantages over North Africa, not least our hotel, which was located in the suburb of Tempe to in the south of the city and had air conditioning and a swimming pool. Unfortunately we didn’t have much time to use the pool, but it was a real luxury compared to what we were used to. When you spend the whole day taking measurements inside a car in 75 to 80 degrees heat (mostly without any air conditioning), you get back to the hotel exhausted in the evenings and fall straight into bed.

I still got to enjoy the simple pleasures of North Africa, as commercial vehicle testing continued out there for a number of years. But America made a great change,  with its high-quality hotels and typical American service, lots of things to do, evening entertainment options and all-round more modern facilities.

We had found a test track to in the south of Tempe that was used at the time by the company IHC for testing lorries, trucks and front loaders. You could only drive around the track in a clockwise direction and a cloth was tied around a post at the start line to indicate when someone was already on the circuit. This meant you could always see how many vehicles were out on track at any time.

The test track was long enough but unfortunately it had some very steep, narrow bends, which made it difficult to drive round at top speed. You really had to hold your nerve out on the track! The track was also designed for testing trucks, not catering for the ever-increasing speeds of passenger cars. It therefore was not really suitable for the constant speed tests that were mandatory at the time. For this, we had to use the stretch of highway down to Maricopa. Aside from a few bends, the road was virtually straight, but there was one problem: How can you test a vehicle at a constant speed of 100 kilometres/hour on a road where the speed limit is 70 kilometres/hour? The police came past a few times to pay us a visit…

The different climate also caused us a some difficulties. In North Africa it was hot, but in the evenings and at night temperatures dropped significantly. In Tempe, temperatures soared to their highest point at around 2:30 pm but at 9:00 pm they were still as high as 37 degrees. This impacted on our ability to run our tests. In 1978 – in my opinion the pioneering transition period between carburettors and new fuel mix systems – the measuring technology still had its niggles. For instance, in order to carry out our tests with cooled fuel, we had to cool the fuel cans using large blocks of ice delivered each day by a small delivery truck.

The instruments for measuring different engine temperatures were also temperamental when subjected to the high temperatures in the vehicles. We therefore often had to repeat measurements in the afternoon and right through the evening, including on Saturdays. So our only time off was on Sundays.

Still, we made the most of it! The vast majority of the team spent their Sundays by the hotel pool. Personally, I always preferred to get out and explore the country and its people, and luckily I always found someone willing to come along for the ride. There was so much to enjoy: fantastic cars, enormous shopping centres, endless vistas, plains and forests. I visited the Grand Canyon, the Apache Trail in the east, Nogales, the wild west town of Tombstone in the south, the Canyon de Chelly in the north-east, and much more besides! The itinerary was always the same: Set off on the Saturday night, camp overnight in a forest or on a campsite, and then return again on Sunday. I have very fond memories of driving the ‘road with 3000 bends’ near Alpine in the east with Bernd H.. Jürgen S. and I searched for gemstones in the mountains of the Mogollon Rim and Erich F. and I visited Lake Havasu City and the Colorado River. Together with Hartmut H. I explored the wilds of the Prescott forest and with Kurt K. I discovered the Sedona meteor crater. And Ludwig St. and I enjoyed a wonderful flight over the Grand Canyon… I could go on! Needless to say, every trip was a real adventure and a great respite after a long working week in the south-west of the USA.