The science behind that jumbo wheelbase
--F.M.
The 612's ultra-long wheelbase makes it look a bit awkward from some angles, despite the "Ingrid scallop" used to disguise it, but Ferrari's engineers deemed it vital to approach the target front/rear weight distribution of 45/55. (The final distribution ended up 46/54.) That target was established after extensive testing on the effect of weight distribution on acceleration, handling, and braking, the graphic results of which are illustrated on this page.
Acceleration performance was found to improve markedly as the percentage of weight on the rear tires increases beyond the 40 to 50 percent most GT cars employ, before leveling off between 55 and 60.
The steering-wheel angle required to maintain a given lateral g load varies noticeably with weight distribution. At 0.90 g, the mule with the 55-percent rear bias required 28-percent-less steering input than the one with a similar front weight bias. Less steering input means less understeer, better handling, and improved tire wear.
Weight shifts forward under braking, which diminishes the amount of retardation the rear wheels can provide. At 0.90 g, the rear-biased mule's rear brakes were generating 64 percent as much retardation as its front brakes, whereas the front-biased mule's rear brakes could only manage 41 percent as much braking as its front brakes. The more evenly split the brake force, the less fade and the more confident the brakes feel.