CR toploader w/ 3.08 or 3.31 rear diff?

[Ant]

It all depends on tire size and where your engine power is, a friend of mine has a Cobra with 450bhp 390 cu in engine, and the CR Toploader, going to a 3.08 rear end, and then 26.5" diameter Toyo tires. My recommendation was to go to a wide space Toploader, as first gear on the CR is sort of good for over 60mph @6500rpm maximum. He went for a good strong paddle type dual lining clutch, so time will tell on how the clutch will handle the gearing, the cars are reasonably light and he is doing mainly road cruising!

On the other hand I have a 675bhp 373 canted valve Ford engine, in a very lightweight car with five speed Jerico, first gear is 2.906, which I chose to give me a bit of take off driveability both on the road and track, fifth gear is 1.1, going to a 3.27 on 25.6" diameter rubber, this gives me 60mph at around 2500rpm, and about 6600rpm at the end of the straights on my local race tracks, as this gives me a reasonable cruising speed, I may have to go to a 3.50 rear end depending on how the car behaves around the circuit, gearing a car for road and race is difficult, I thought by having five speeds that will help but trial and error with tell the story. With the speed limit in NZ and the amount of cars on the road I will go for more acceleration than top speed.