A couple of my favrouite shitboxes would be the following:
Hispania-Cosworth(Dallara)h F110:
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Second worst car of the year, but id be happy to take one for a run id say
Super Aguri-Honda SA05/SA06:
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Moving chichanes in 2006 however, were based on 2002 technology
Midland-Toyota MF1:
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Same as the Superaguris above, but worse as they were upto date at the time, however based largly on the last Jordan
BMW.Williams FW24:
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Failure because of the nose design. Was redesigned for last third of 2004
Bennaton B201:
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The car was generally a decent one, but due to badly out of date design structure and tunnel Gasgoyne had to fix the whole team to move forward. The car that started the (faint) linage to the R25 and R26 in effect.
Mastercard Lola-Ford T97/30:
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The ultimate --- box, they qualified 11.603 and 12.717 respectivly off the pace. At least Hispania made it look better with a car that was hardly tested.