"Speed per Dollar" index

[One 328is]

It occurred to me that enthusiasts could use a new equation to better quantify a vehicle’s capabilities in view of its cost—something like horsepower-per-pound-per-dollar, a metric that more artfully balances power, weight, and financial outlay. Thus, the “Speed per Dollar” concept was born.

Being something of a buffoon at mathematics and graphics, I sought help to turn the idea into a meaningful standardized equation that would yield useful numbers. The staff at WINDING ROAD rallied around the concept and contacted the fine folks at Funnel Inc. (motto: “Information design that makes the complex clear”), and the concept became a reality.

The basic calculation they came up with is as follows:

(Horsepower ÷ Weight) x 10,000 ÷ Price Point x 100,000 = SpD

We think this SpD metric is uniquely useful because it weighs a vehicle’s accelerative capabilities against its cost. There’s no doubt that the Bugatti Veyron 16/4 is a tremendous technical achievement, but as a value proposition, well, it fails miserably—a development that should come as a shock to exactly no one given its plutocratic price tag.

We like the SpD because it celebrates affordable sports like the Mazdaspeed3, Chevrolet Corvette, and the Ariel Atom. It isn’t perfect (it doesn’t take into account a vehicle’s handling envelope), but nevertheless, we think it’s a better evaluation of enthusiast vehicles than existing calculations.

A few sample equations:

2007 Ford Mustang GT: (300 hp ÷ 3356 lbs.) x 10,000 ÷ $26,370 x 100,000 = 3390 SpD
2007 Lotus Elise: (190 hp ÷ 1984 lbs.) x 10,000 ÷ $42,990 x 100,000 = 2228 SpD
2007 Saleen S7 TT: (750 hp ÷ 2950 lbs.) x 10,000 ÷ $580,000 x 100,000 = 437 SpD



Link
Winding Road » Archive » A New Performance Paradigm: The ‘Speed Per Dollar’ Index


Thought this would be an interesting topic to talk over.

[CraigMakDaddy]

This is pretty tite. Now calculate the e36 M3, e46 M3 and various other bimmers. Let's see how they fair in the equation. It's very interesting.

[CraigMakDaddy]

Here is a much easier way to put this calculation:

[Scorp965]

interesting...

My turbo nsx has the following attributes...
390rwhp = ~440hp
2890lbs
$60,000 build cost, including car

= 2537.49 SpD

so... a bit more-practical than a Z06, but not as practical as a mitsubishi, yet it has the same power/weight ratio as the Ariel Atom.

[CraigMakDaddy]

Your NSX doesnt really compare to these figures because it is a used car if it cost you less than $120K to buy. Do the math on a brand new un modded NSX. A used e36 M3 is (240hp)(10^9)/($17,000)(3250lb) = 4,344 SpD
A used e46 M3 is (333hp)(10^9)/($30,000)(3400lb) = 3,265 SpD
My 328i comes out to (200hp)(10^9)/($16,000)(3000lb) = 4167 SpD
As you can see, it is unfair to compare used cars to new cars because all of these SpD figures are crazy.

A brand new e46 M3 is (333hp)(10^9)/($48000)(3400lb) = 2,040 SpD
A new 760Li gets (438hp)(10^9)/($122,600)(4905lb) = 728 Spd LOL

[Duke]

1990 Yugo

HP = 50 BHP
Weight = 1984 lbs
Price = $5000

SpD = 1/5040


The clear winner.

[Highboosted]

My Stealth has a SpD of 9,424.6 with it's current cost

If you factor in it's new cost in 1994 it comes out to 2537.7 (with everything stock).

This is a good idea but is basically useless. Doesn't factor in things that matter on the track and on the road. A vastly simplified way to rate cars, however doesn't actually measure anything: just because a car is either light or has lotsa HP doesn't make it fast round a track. I can harrass a new Porche 911 GT3 on a track, doesn't make it a worse car than mine (or mine a better car).

Just did a buddy's Mustang he just built. SpD of 34,478, but it can't turn for crap (drag car), and has no creature comforts.

[CraigMakDaddy]

Originally Posted by Highboosted

My Stealth has a SpD of 9,424.6 with it's current cost

If you factor in it's new cost in 1994 it comes out to 2537.7 (with everything stock).

This is a good idea but is basically useless. Doesn't factor in things that matter on the track and on the road. A vastly simplified way to rate cars, however doesn't actually measure anything: just because a car is either light or has lotsa HP doesn't make it fast round a track. I can harrass a new Porche 911 GT3 on a track, doesn't make it a worse car than mine (or mine a better car).

Just did a buddy's Mustang he just built. SpD of 34,478, but it can't turn for crap (drag car), and has no creature comforts.

Yeah, I agree. I did the calculation on a crappy Toyota Yaris and that dumb thing got a rating of 4151 SpD. Extremely cheap cars with very low hp have a huge advantage. If only there was a handling index or something.

[CraigMakDaddy]

According to TopGear the Ariel Atome has 300hp using a turbo charge Honda Civic Type R engine not 205. So, WOW!! it should have an insane score

[Nitrious]

my 318is:

(160/2645)*10000/4400*100000=2,6*10^11 SpD

[CraigMakDaddy]

Originally Posted by Nitrious

my 318is:

(160/2645)*10000/4400*100000=2,6*10^11 SpD

This car's SpD comes out to 3636 SpD. (160hp)(10^9)/($10,000)(4400) = 3636

[CraigMakDaddy]

Originally Posted by Duke

1990 Yugo

HP = 50 BHP
Weight = 1984 lbs
Price = $5000

SpD = 1/5040


The clear winner.

WOW!! The Yugo ownz LOL
(50hp)(10^9)/($5000)(1984lb) = 5040 SpD LMAO

Yeah, this equation simply doesn't work on economy cars. Thier extremely low prices totally throw it off.

[tdc]

I would think this equation only makes sense on vehicles that are considered "sporty". Who cares what the SPEED per dollar quotient is on an economy car? That's why the numbers are all out of wack when you try it on one.

[Nitrious]

who cares about the real speed anyway, it's all about the feel of the car

[Nitrious]

Originally Posted by CraigMakDaddy

This car's SpD comes out to 3636 SpD. (160hp)(10^9)/($10,000)(4400) = 3636

slight misscalculation by me, i think