Having driven many cars with between 100 and 900 horsepower...

Having driven many cars with between 100 and 900 horsepower, I can safely say that the perfect daily driver has 400 horsepower.

>never ever feels lacking when merging or passing
>fast enough to be thrilling but not frantic enough to be scary or unwieldy
>lots of pep for driving around town normally, but won't look like your trying to race people on a quarter throttle
>won't accelerate so fast you can't enjoy the speed without risking jail
>doesn't need expensive and uncomfortable extreme performance tires to put down power, UHP is fine
>more than enough for autocross or track duty

100 is borderline unsafe, 200 is sufficient but not exciting, 300 to 500 is all pretty good, 600 is when power starts becoming useless, 700 and above is just scary and unreliable.

Assuming similar torque and average weight/gearing

the fastest car ive driven was a focus st. and that felt slow :(

3000 lb sports cars should have 500 crank horsepower

I think it depends entirely on where you live as well as what kind of HP we are talking. Big lumbering engines with lots of power are not as suited to roads that require a lot of throttle modulation. In contrast, that would be perfect for highway situations or places that are fairly straight.

Point is, there is no perfect number, and far more factors that contribute to perceived speed and power than just the number of ponies an engine puts out at a given rpm.

15lbs/hp is fine.
10lbs/hp is fun
5lbs/hp is silly fun
2.5lbs/hp is helium exit bag
1lb/hp is super alcohol burning funny

Completely depends on the body, weight, configuration, brakes, suspension and traction.

C5z would be a horrible daily driver

t. C5z owner

Whats wrong with it im looking to buy one next year

so they should all be slightly more powerful .pw ratio than a c6 z06?

Never driven a car over 320whp but seems like a pretty knowledgeable post. Don't know why you would ever really need more then 400 HP on a DD