Think about riding a ten speed bike. You line up next to your twin brother, both of you on your identical ten speed bikes. Each of you are just as strong as the other. You start the race in 5th gear and your twin starts the race in 10th gear. You race for 20 ft, who do ya think will win? You will, although eventually he will be able to pass you on the top end you will be able to out accelerate him. The gear in your diff is the same concept of why you will accelerate faster with the 3.9 as opposed to the 3.54. It should feel like an instant 30 hp gain!
> Actually, I think it is the driveshaft will
> rotate 3.9 times for every 1 revolution of
> the drive wheel. I'm not an expert or
> anything myself, but I think this is right.
> You would get better acceleration but have
> to shift sooner. If your car barley gets to
> 60 in 2nd before loosing power, getting
> redline, then if you lowered the overall
> ratio, youd have to make one more shift.