Chaparral 2J 1970

[McLareN]

The "rocket" Chaparral.

BTW, If theres anyone interested in other Chaparral just let me know.

Chaparral 2J #1:

[nopassn]

at Leguna Seca this year they had a hard time keeping the ancilary engine running that runs the fans/sucker on this car, but it was hella cool to see once they did finally get it "sorted out"

[henk4]

at Leguna Seca this year they had a hard time keeping the ancilary engine running that runs the fans/sucker on this car, but it was hella cool to see once they did finally get it "sorted out"

Well, the engine ran, but only when the car itself was not moving. It made a lot of noise in the pitlane, but did not want to keep going. The demonstaration laps then were done with the JLO engine off. The engine sucked (not really:D )

[forza_autodelta]

that's the kind of race cars you 'll never be able to use when you would

[Lagonda]

What kind of an engine did it have anyway ? What was the point of the fans ? Sort of forced induction ?

[henk4]

it was twin cylinder JLO two stroke engine, giving about 50 BHP. The purpose was to generate a vacuum underneath the car, hence the skirts at the bottom.
Brabham tried the same in formula i with the Brabham Alfa Romeo, but that system got almost immediately banned by FIA, after the first race had shown that it had worked perfectly:)

[TVR IS KING]

yep. snowmobile engine behind the other engine, which was behind the driver. it was once said that you could take any line you wanted, not the traditional line, it didnt matter! they literally sucked the car to the ground for traction.
its on GT4 but ive never driven it.

[Lets Gekiga In]

Thanks for fulfilling my request, McLareN!

[Matra et Alpine]

Here's Jackie in 1970 Can Am race ( sorry it's not 1024, but I thought worthy to show the MAN driving the beast )

[henk4]

Almost a period shot. Being towed away after the Laguna Seca Chaparral photo shoot..

[McLareN]

Almost a period shot. Being towed away after the Laguna Seca Chaparral photo shoot..

Amazing photo Pieter! Two thumbs way up.

[islero]

Hey Mclaren, I need pics of the other Chapparals too, especially 2A. Can you please post em up?

[Ferrer]

Chaparral 2J #4

[Matra et Alpine]

Stumbled across this and I had not realised how noisy the fan engine was :)

http://www.youtube.com/watch?v=HZkUr5cG6wE

[Ferrer]

The most unusual Chaparral is the 2J. On the chassis' sides bottom edges are articulated plastic skirts that seal against the ground (a technology that would later appear in Formula One). At the rear of the 2J are housed two 17-inch, JLO (pronounced "EE-lo") fans driven by a single 45 hp two stroke twin snowmobile engine. The car had a "skirt" made of Lexan extending to the ground on both sides, laterally on the back of the car, and laterally from just aft of the front wheels. It was integrated with the suspension system so the bottom of the skirt would maintain a distance of one inch from the ground regardless of G forces or anomalies in the road surface, thereby providing a zone within which the JLO fans could create a partial vacuum which would provide a downforce on the order of 1.25-1.50 G of the car fully loaded (fuel, oil, coolant). This downforce, materially greater than the weight of the car, had one journalist remark—literally quite accurate—that the 2J, which weighed less than a ton, with its JLO motors running and generating their downforce of 1+ G could have been unveiled to the public on the ceiling. This gave the car tremendous gripping power and enabled greater maneuverability at all speeds. Since it created the same levels of low pressure under the car at all speeds, down-force did not decrease at lower speeds. With other aerodynamic devices, down-force decreases as the car slows down or achieves too much of a slip angle, both of which were not problems for the "sucker car".

The 2J competed in the Can-Am series and qualified at least 2 seconds quicker than the next fastest car, but was not a success, because it was plagued with mechanical problems. It ran for only one racing season, in 1970, after which it was outlawed by the Sports Car Club of America (SCCA). Although originally approved by the SCCA, they succumbed to pressure from other teams, McLaren in particular, who argued that the fans constituted "movable aerodynamic devices", outlawed by the international sanctioning body, the FIA, a rule first applied against the 2E's adjustable wing. There were also complaints from other drivers saying that whenever they drove behind it the fans would throw stones at their cars. McLaren argued that if the 2J were not outlawed, it would likely kill the Can-Am series by totally dominating it — ironically, something McLaren had been doing since 1967. A similar suction fan was used in Formula 1 eight years later which won the 1978 Swedish Grand Prix, by the Brabham BT46B, but was withdrawn soon after due to complaints from other teams that the car violated the rules. The car was found to be within technical specifications allowing the victory to remain.

Source: wikipedia.org