2019-04-15 11:13:49 | pauls writes:

Russian article about this car at:

jaguarrules.ru/jaguar-xj27-experimental-18/

Best translation I can do.

Jaguar XJ27 Experimental # 18 is one of the variants of the prototype XJ27 (future XJ-S), which was not destroyed and is distinguished by its unique features.

During the development of the Jaguar XJ27 from 1969 to 1975, many different experimental branches were built. Model Jaguar XJ27 Experimental № 18 is one of the test options for the future Jaguar XJ-S. This car has become an object for testing a completely different cooling system.

With its cooling system, the car was similar to many Italian GT produced in small series. This cooling design was popular at the time, and most likely it was for this reason that the Jaguar XJ27 Experimental No. 18 was created as a springboard for testing this way to cool the powerful V12.

The Jaguar XJ27 Experimental # 18 came off the assembly line on June 10, 1975, exactly three months before the official presentation of the new XJ-S. It was also the first copy of the XJ-S exported to the United States in August of the same year to continue testing in the New York area, as well as in the desert areas in the southwest United States. The car was registered under the LDU number 862P on behalf of the Jaguar Research and Experimentation Division.

The changes made to the LDU 862P coupe were intended only to adapt to the predicted future standards in different US states regarding noise and emissions standards. This was done by separating the engine compartment in order to better isolate the engine from the environment and make it less audible. Changing the position of the radiator and cooling the engine with directional flow were only a consequence of this study. These decisions were not made in the extended Jaguar, but were an initiative from the only Malcolm Oliver, the technical director of Jaguar Cars in North America.

On the experimental compartment, the water radiator is located almost horizontally, just below the wide opening created in the upper part of the bonnet. The front of the radiator is slightly raised, and the surface of the radiator is slightly reduced compared to conventional dimensions due to the overall efficiency of the new system. Circulating airflow improves in cooling when the engine is running with a stationary car, but despite this, two electric fans with a thermostat are installed above the radiator.

Due to the addition of a fixed air outlet grille, the size of the bonnet has been reduced by 45 centimeters. The front of the car is made in the form of a solid panel and can be disassembled to access the radiator. The partition was also placed directly in front of the engine to close the compartment surrounding it.

A bottom plate was also planned to protect the engine, but the idea was not implemented. Motor protection, under certain conditions, led to an increase in temperature in this area. In any case, a small electric fan was installed in the compartment to solve this problem.

It is known that after the car was delivered to the USA in August 1975, it was immediately started to be tested hard. Testing involved Oliver himself. There were about 20,000 kilometers, of which about 4-5 days in New York, and then 3-4 weeks in the wild heat of Arizona. After the trip continued in New Orleans, which allowed us to test cooling in conditions of heat and humidity.

Throughout the test, the Jaguar XJ27 Experimental No. 18 was equipped with 48 thermocouples to measure temperature and other parameters in all corners of the vehicle.

At the moment, we can only assume that the implementation of these tests was too late. Changing the cooling system was impossible due to the fact that the car was actually in production, and less than a month remained before its announcement. All changes could occur only with the next series upgrade.

As Malcolm Oliver noted, tests of the cooling system began in 1972, but until 1976-77 they were not carried out at temperatures above 50 degrees. Oliver was also proposed changes in the air conditioning system, which, unfortunately, managed to translate only later. In general, the result of all the tests turned out to be quite predictable.

All further modifications of the “number 18” were made around 1976 in order to solve possible future problems associated with the release of the new XJ-S. According to Oliver, Jaguar was in no way intended to test the new front of the car and follow the design of the Italian GT at that time.

At that time, these modifications were implemented only for experimental purposes and the car also had its drawbacks. For example, the driver’s vision through the windshield was slightly disturbed due to the distortion created by the hot air coming out of the grilles on the hood.

Naturally, such experimental models are not intended for sale. It is assumed that one of the engineers of Jagaur who participated in the creation of the model offered to buy out the Jaguar XJ27 Experimental No. 18 immediately after the tests.

It is reliably known that in 1985 the model was brought to the USA to become the property of a collector who bought it through his contacts in Britain.

The car was used for a while by the new owner, but was then exhibited at the state museum in Vermont. Ironically, the reason for stopping trips to the model was that the engine seemed to become overheated.

2019-04-18 10:59:21 | pauls writes:

We do not believe this car is 2W/1018, however based on the above article's ID and no positive ID we will leave it here. Please contact the webmaster with any updated information.

2019-10-03 09:12:01 | Andy S. writes:

I would agree. XJ27/18 probably received a random serial number when it was sold. For comparison, XJ27/16 got serial number UF2W50028BW in May of 1975, so they could export it to the United States for testing.

2020-07-23 13:52:32 | Steve Davis writes:

According to Rivers Fletcher's book (page 31), experimental number 18 was body number 5W1015, and registered LDU 862P. Unfortunately, no chassis number is listed. Car was British Racing Green, automatic and left hand drive, so I wonder if it would have been given a UF2W50xxx chassis number? A list of other early vehicles assigned to the experimental department is given on the same page.

I hope this helps someone.