300mph C5???
12-07-2005, 02:56 AM
#41
Le Mans Master
Originally Posted by UncleRobb
Here's the math:
The power P needed to reach a speed v in a car is approximately proportional to the cube of the latter,
P ~ v^3......................(1)
With
P' ~ v'^3.....................(2)
and dividing Eq. (1) by Eq. (2) and multiplying both sides by P', we get a formula to estimate the power P needed to achieve a speed v when the car reaches a speed v' with a power P'
P = P' (v/v')^3..............(3)
Thus, with P'=350 hp, v'=175 mph, and v=300 mph, we get P=1763 hp. Moreover, we may solve Eq. (3) for v, to obtain the top speed at a given power P,
v = cube root(P/P') v'.....(4)
With P=992 hp, P'=350 hp, and v=175 mph, we get v=248 mph. Remark: I used engine powers instead of rear wheel powers. However, assuming that the losses in the drive train are proportional to the engine power, the above calculation is unchanged if we insert rear wheel powers for P and P'.
Its great to be a theoretical physicist
The power P needed to reach a speed v in a car is approximately proportional to the cube of the latter,
P ~ v^3......................(1)
With
P' ~ v'^3.....................(2)
and dividing Eq. (1) by Eq. (2) and multiplying both sides by P', we get a formula to estimate the power P needed to achieve a speed v when the car reaches a speed v' with a power P'
P = P' (v/v')^3..............(3)
Thus, with P'=350 hp, v'=175 mph, and v=300 mph, we get P=1763 hp. Moreover, we may solve Eq. (3) for v, to obtain the top speed at a given power P,
v = cube root(P/P') v'.....(4)
With P=992 hp, P'=350 hp, and v=175 mph, we get v=248 mph. Remark: I used engine powers instead of rear wheel powers. However, assuming that the losses in the drive train are proportional to the engine power, the above calculation is unchanged if we insert rear wheel powers for P and P'.
Its great to be a theoretical physicist
12-07-2005, 03:37 AM
#42
Le Mans Master
Originally Posted by bobdt173
I would think its possible. LPE puts out 800hp C5R motors that top out around 230-250ish. If you would put a TT or a maggie on it you would have a beast. Alot would depend on what gears you were running also. To do 300mph the car would have to have some major body mods to hold it to the ground. I think the stock body is only rated to 200mph. This is only an opinion take it for what its worth.
Bob
Bob
sort of like what happened here:
http://video.google.com/videoplay?do...28604468&q=rx7
12-07-2005, 09:57 AM
#43
Le Mans Master
Originally Posted by scott_fx
sort of like what happened here:
http://video.google.com/videoplay?do...28604468&q=rx7
http://video.google.com/videoplay?do...28604468&q=rx7
12-07-2005, 10:01 AM
#44
Le Mans Master
I wonder if a stock bodied, moded HP Viper could do it. It actually has functional under car ground effects. I'm not sure if that is the correct term, but they are functional.
12-07-2005, 11:24 AM
#45
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As a C4 owner thinking of "upgrading" to a C5, I find this thread very interesting. Amazing to me what a few individuals could do back in 1988 with an almost stock bodied C4.
http://www.callawayownersgroup.com/C...ember/cotm.htm
http://www.callawayownersgroup.com/C...ember/cotm.htm
12-07-2005, 12:10 PM
#46
Le Mans Master
Originally Posted by Wile'sVette
As a C4 owner thinking of "upgrading" to a C5, I find this thread very interesting. Amazing to me what a few individuals could do back in 1988 with an almost stock bodied C4.
http://www.callawayownersgroup.com/C...ember/cotm.htm
http://www.callawayownersgroup.com/C...ember/cotm.htm
12-07-2005, 12:16 PM
#48
Originally Posted by scott_fx
sort of like what happened here:
http://video.google.com/videoplay?do...28604468&q=rx7
http://video.google.com/videoplay?do...28604468&q=rx7
"Hey Mom, I'm running to the store - I'll be back real quick."
12-07-2005, 12:51 PM
#49
Le Mans Master
Originally Posted by StevieB
That is what looks to be a short flight ricer.
and the stickers were actual sponsors
12-07-2005, 07:15 PM
#50
Le Mans Master
Originally Posted by scott_fx
that wasn't a ricer car, but the racing beat landspeed record (for a stock chassis car i think) to which they eventually accomplished. Just because it's not a domestic, doesn't mean it's rice and the stickers were actual sponsors
and the stickers were actual sponsors
12-07-2005, 07:38 PM
#52
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300 That all depends on what color it is. Plus if it's on the internet it's got to be true. I'll be at the auction all week so I'll keep an eye out for it. I'll be the guy in the back calling 
when bids start
when bids start
12-08-2005, 06:27 PM
#53
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Originally Posted by StevieB
Everybody knows what you just said. I figured it out on my Texas instruments calculator years ago.
12-08-2005, 06:40 PM
#54
Safety Car
Originally Posted by sxe60
You'd probably have to double the horsepower to achieve the additional 60mph, because of drag horsepower becomes inversely proportional to speed.
12-08-2005, 07:28 PM
#55
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Originally Posted by fdxpilot
To use the Bugatti as an example, if 1100hp goes to 253, to get to 300 (253x 1.1858) would require 1.406 x 1100hp, or 1547hp. And that's only based on aero drag, not tire friction. Still, 1547 hp in anything but a top-Fuel dragster is ridiculous to even think about. Even that 1100 hp takes a 8L quad-turbo W-16 engine. 300 out of a C5 is a fantasy.
1.) No tire on the planet that fits a street car rim can support 300 mph.
2.) The Vette would need a serious downforce pkg. to stay planted with the slightest of bumps. Edit: So we may need an aero downforce pkg. that nets a Cd of 0.35 or worse which will mean more than the 12xx rwhp quoted earlier. This added drag force substantially and increases hp requirements for 300 mph to the point where I doubt even a C5-R built motor will hold together long enough to reach 300 mph with the frontal area x Cd of the Vette.
Last edited by STAGED; 12-09-2005 at 12:32 PM.
12-08-2005, 10:24 PM
#56
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Originally Posted by fdxpilot
Actually, power required to overcome drag is proportional to the square of velocity (from my Aero Eng background). To use the Bugatti as an example, if 1100hp goes to 253, to get to 300 (253x 1.1858) would require 1.406 x 1100hp, or 1547hp. And that's only based on aero drag, not tire friction. Still, 1547 hp in anything but a top-Fuel dragster is ridiculous to even think about. Even that 1100 hp takes a 8L quad-turbo W-16 engine. 300 out of a C5 is a fantasy.
12-09-2005, 01:36 AM
#57
Safety Car
Originally Posted by UncleRobb
I am afraid that this is not quite right. E.g. have a look here for a NASA publication on a vehicle's energy balance.
12-09-2005, 06:18 AM
#60
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Originally Posted by fdxpilot
Even worse, the cube of velocity!! In my defense, it's been years since I had to do any of those calculations for real. Anyway, it requires way too much HP to get to 300mph.