How Much HP Do You Really Need???
 

I am as guilty of this as anyone, but how much HP do you really need in the real world??? We get consumed by 0-60 times, etc. But what makes for a really fun car in the real world??? I know I don't drag race between lights.

My answer would be a light car with decent hp. If I were to pick a car I wanted more than the RX-8, it would have to be the Elise, in regular or SC form. That car weights around 2000 lbs. The problem with the Elise is that it is a total toy and totally impractical. The RX-8 can perform everyday duties while being fun. The Elise would stay in the garage until a sunny warm day.

Aside from toys like the Elise, the RX-8 is already one of the lighter cars on the market, particularly if you talk about a car with any real practicality. I know the current RX-8 is dead in the marketplace for all practical purposes. But, in the real world in real world driving conditions, is a RX that is much more powerful or much lighter going to be THAT much more fun to drive day to day???

10 to 1.

So an RX8 with 300 crank HP would be perfect for a DD, anything more is wasted unless you get it on a track. Not wasted 100% of the time... but 99.9999% of the daily driving I do I never go WOT.

All depends on where you drive and what traffic is like. For me, no it won't make a difference because it's an overpopulated rich upper class yuppie neighborhood I live in. We get traffic being near the neighboring state all the time and it's freaking ridiculous. Takes me 30 minutes to go 10 miles to get to work.

Only on the highway or trips is it worth it but I'm content with what I got..................













Until I move back to the boonies.

Define much more. Kane's answer of 300rwhp is very good. There are tons of rave reviews from turbo owners at ~300rwhp that say the car is exponentially better than stock.

Personally, I agree with the sentiment wholeheartedly. The car is already great around corners; giving it a bit more straight-line speed would be the tits. Especially if I don't have to shift down to 4th just to pass people and climb uphill.

We always want more than we have. When I first drove the '8 I was impressed with its "pick up.' But of course later in my life with the vehicle I find myself wanting more, even tho' I know I have enough for my typical street-spirited driving. I've NA modded my '8 about as much as I'm willing to do short of an engine rebuild/porting (better intake and exhaust flow, Cobb AP tuned by MM, BHR iginition). I endlessly evaluate FI and Nitrous, but just as endlessly overide my impulse with the practicality of overall reliability and frugal consideration of ease of resale (or ease of potential engine replacement should the need arise). I still may go Nitrous this season tho'..... ;)

Personally, 1:9 is the ratio I use for a street car.
You really can't find a situation on the road where you will, shall we say, "be sad" with a 1:9 power to weight ratio.
On the RX-8 that is about 350 HP.

I dont go WOT all of the time and I live in an area without that much traffic. So honestly if the rx8 would have just a little bit more hp, like the greddy or pettit to put it close to 300 that would be great in my opinion.

Kanes got it right when he says much past that you really just wasted money unless your going to track it

In my flying days I was satisfied with a greater than 1:1 thrust to weight ratio. That's all you need to accelerate ballistically. ;)

300 rwhp is pretty amazing in the rx8. Like heaven on earth.

What I think is actually more relevant for a daily driver is ; how much torque do you really need ? Somewhere around 200+ ft/lbs in the 3-5500 range seems like plenty to me . Most of your daily driving is in that range .

300whp at 7500rpm is something you utilise infrequently (unless you are a nutter) although that does seem to be a good benchmark.

^ true that Brettus. In traffic our superb maneuverability is a plus, but really needs to be further augmented by a bit more torque. I've always considered myself an offensive driver in that I try to preemptively avoid potential hazards (e.g. poorly skilled drivers as well as road). I rarely need off the line or top end speed, but often need more rapid at-speed acceleration.

I am going to kill myself....

:confused:

A) Torque does no work

B) Torque times rpm ======== horsepower!

Why bring up irrelevant information?

Since I am too lazy to type.

http://www.carcraft.com/techarticles...que/index.html

Torque is overrated. :D:

If you were going to look at it that way what number would you say is good in the 3-5500rpm range ?
You can't give me a single number , which is why torque is relevant when talking mid range .

Really.

I don't understand the last two points.

Torque is the primary engine characteristic from which the more talked-about horsepower value is derived, as Kane points out.


As far as torque being "overrated", the area under the torque curve, as well as its distribution is an indicator of an engine's performance; just compare two strokes and four strokes of similar tune and see where the power lies.

Gains in high end rpm typically come at the cost of low end torque without some type of manifold pressure boosting system or variability in combustion timing. High torque motors generally achieve maximum hp before maximum rpm, but can drive a higher gearset.

The way I see it, what matters is not horsepower, but how it's made and how well it suits your needs, and that all is based on... torque.

Yeah I can...

On a street driven car, I would want to make 175HP by 3500 RPMS and make 300HP by 7000 RPMS.

Guess what the torque curve for that would look like?

What car is faster? 100 HP with 9000lb/ft of Torque or a 9000HP with 100lb/ft of Torque? Same gearing.

These motor-head heuristics are annoying.

"Torque does the work, but horsepower gets the credit."

"Horsepower sells cars, but torque wins races." - Carroll Shelby

:)

Well he is wrong...physics is on my side.

torque vs. horsepower = turbo vs. supercharger ;)

torque vs horsepower = boost vs flow


:lol:

http://static.howstuffworks.com/flash/fpte-curve2.swf

This is cool illustration of what I am trying to say.

I actually drove down (and up) the street yesterday in 2nd gear, just shy of the rev limiter, for about 2 minutes.
Does that make me a nutter?

Oh no. Here we go again.

Torque does ALL the work. Horsepower IS work, it doesn't "do" it.
Time is what makes force INTO work.
Torque, utilizing the TOOL that is TIME creates work.
Horsepower is a measurement of the work that torque does.

That is what mucks up your assertion.

If you geared each of those motors appropriately, they would be completely equal.