The F1s in the game, regardless of age, all have much better HP-to-weight ratios than anything else. True, the LeMans racers approach this HP-to-weight ratio and approach the F1 cars in handling, but they are not better in either of those categories. And, by default, they are not better cars. I guess the LM cars might make you 'feel' better.
Take a look at HP-to-weight ratios for your cars. It is THE definitive number to crunch when deciding on speed. The lower the ratio (the lower the #), the faster the acceleration and generally (gear ratio dependant) the faster the top speed. Remember, HP isn't the only judge. A 400HP car can beat a 600HP car, if it has the weight advantage.
The F1s are in the low .600-.700 range. The GT-One, R390, 787, are in the .700-.800 range. They are a bit slower. The Escudo is some ridiculously low #. Interestingly enough, the Speed 12 with maxed out HP is in the .800 range, but it handles essentially like a road car. This explains why it is much more difficult to drive than most cars in the game. Corvette C5R, Camaro Race Car, RX7-LM are about 1.100.
Another comparison. A stock 3000GT Turbo, which we can all agree is a fast road car, is about *5.500*. It really puts things in perspective.
Most important and first upgrade to any car should be: weight reduction.
