I think the main problem these cars have with doing fast 0-60 and 0-100 times are 3 folds:
1) Most important is tire size, lack of traction. Tires are ridiculously skinny. No matter how much power you have, if you can't apply it to the road, it's useless. Toni Valenti's car uses very wide Pin drive Halibrand Cobra wheels, 335 at the rear. This is a lot of meat on the ground! not much spinning there.
2) Rear end ratio. The Frua is geared very long from the factory, 2.88 for the auto-box version and 3.08 for the 4 speed model. Gearing it down for racing to let say 3.54 of shorter will increase acceleration substantially.
3) Although Toni's car is still using the C6 box, a 4 or 5 speed transmission will also increase acceleration. However, with a very short rear end the difference is reduced.
With proper tire quality, size and gearing the Frua can easily be made to accelerate as about as quick as a Cobra, the longer wheelbase will also help. The car is still quite light compared to US muscle cars.
Emmanuel[
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