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OK, the other day I was browsing through Suprastore.com. I clicked on the supras for sale button. I scroll through the pictures admiring the sick ass cars, then I see this black supra. The site said that the car is capable of 220mph. I'm thinking its all bull, but I was wondering what the forum had to say about it. If it is possible can someone tell me how, thanx.





Shawn
 

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LOTS of single turbo Supras are capable of 220 mph. It all depends on gearing. Raised RPM limits and larger tires will help and of course if you really want top speed higher gearing.

Think about it, a 380 RWHP Supra can do about 185 mph or more, so imagine a 650 RWHP Supra with higher gearing and a good set up or especially the 1200 RWHP MVP Supra!!! :eek: :eek:
 
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Does anyone know how to remove the rev limiter, or is there any site that gives directions to removing the limiter? Thanx
 

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To double a cars speed you have to quadruple the HP. All forms of resistance, aka friction. For example,

1/2mv^2 =Energy(kinetic)

m=mass
v=velocity

All forms of energy have the same relation, rotational mass is the same. Friction due to air, fluids,..etc. also has the square proportionality. Energy is directly proportional to power.


Let's say it takes a supra 400rwhp to run 190mph, we can guess that if we double the speed to 380mph it theoretically takes quadruple the HP, or 1600rwhp. We can say 220mph drops between 190mph and 380mph. Or 220mph is 15.8% speed increase from 190mph to 380 mph, so hp must increase 15.8% between the difference of 400rwhp and 1600rwhp. Since we said it takes 400rwhp to go 190 mph and 1600rwhp to run 380mph there is a 1200rwhp difference to run the extra 190 mph. So we figure how much hp is 15.8% from 400rwhp-1600rwhp Using 15.8%, it takes an extra 189 rwhp or 400rwhp + 189rwhp = 589rwhp for a supra to run 220mph. This is theoretical, of course this doesn't include gearing change. If you think this is farfetched, with the correct gearing a 560rwhp TT vette hit 240mph . The c5 vette has a better cd(coefficient of drag) of drag then the supra. That's to say if we didn't change any aerodynamics for downforce. Hope this helps.

Sam

PS you can also say a 900 rwhp car like Saad's can move 270 mph but most cars are like airplane wings, air above the car moves faster then air below, by that speed so it would take off w/o major downforce. With downforce comes drag so actually you would need a lot more hp. Also using my assumptions it 285 rwhp supra will only hit 160mph, therefore my calculations are on the conservative side.
 
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BPUKiller said:
To double a cars speed you have to quadruple the HP. All forms of resistance, aka friction. For example,

1/2mv^2 =Energy(kinetic)

m=mass
v=velocity

All forms of energy have the same relation, rotational mass is the same. Friction due to air, fluids,..etc. also has the square proportionality. Energy is directly proportional to power.


Let's say it takes a supra 400rwhp to run 190mph, we can guess that if we double the speed to 380mph it theoretically takes quadruple the HP, or 1600rwhp. We can say 220mph drops between 190mph and 380mph. Or 220mph is 15.8% speed increase from 190mph to 380 mph, so hp must increase 15.8% between the difference of 400rwhp and 1600rwhp. Since we said it takes 400rwhp to go 190 mph and 1600rwhp to run 380mph there is a 1200rwhp difference to run the extra 190 mph. So we figure how much hp is 15.8% from 400rwhp-1600rwhp Using 15.8%, it takes an extra 189 rwhp or 400rwhp + 189rwhp = 589rwhp for a supra to run 220mph. This is theoretical, of course this doesn't include gearing change. If you think this is farfetched, with the correct gearing a 560rwhp TT vette hit 240mph . The c5 vette has a better cd(coefficient of drag) of drag then the supra. That's to say if we didn't change any aerodynamics for downforce. Hope this helps.

Sam

PS you can also say a 900 rwhp car like Saad's can move 270 mph but most cars are like airplane wings, air above the car moves faster then air below, by that speed so it would take off w/o major downforce. With downforce comes drag so actually you would need a lot more hp. Also using my assumptions it 285 rwhp supra will only hit 160mph, therefore my calculations are on the conservative side.


I think you are not using the correct equation to calculate top speed. Mass has small effect on top speed (on cars, not on boats), what counts is drag--aero drag specially. As far as I know, there is no relation between quadruple power to speed; a better relation is: power required is proportional to the square of speed.
 

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I think Car&Driver tested the Lingenfelter 650TT Vette with 570 RWHP and hit 221 mph with higher gearing. For the acceleration tests they used slicks and lower gearing, VERY important details that some people forget. But that's very impressive. The Sledgehammer Vette (C4) hit 255 mph with 920 crank HP.

The C5 Vette must have a great Cd, because the Supra is only 0.33.

As far as calculating top speed goes, it's not a linear thing. The wind resistance/friction don't just increase at the same rate up to insane speeds. It's no problem to increase a car's top speed from 150 to 165 mph, but from 200 to 215 mph it takes ALOT.

This is an overly simple way to calculate RPM at top speed but it will give you an idea. A stock Supra can does 60 mph at 2110 rpm with stock tires. So at the 6800 rpm redline:


60mph/2110rpm=x/6800rpm so the speed x=193 mph

There are things like tire growth at high speed, etc. that would change it though.

for 220 mph:

2110/60=RPM/220 RPM=7735
 

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97SuPrATT said:
Does anyone know how to remove the rev limiter, or is there any site that gives directions to removing the limiter? Thanx

Supposedly pulling the TRAC fuse (under hood fusebox) will remove the top speed limiter, it does not remove the rev limiter. To do that you need to have your car's ECU modified. If you try for top speed don't blame me that you either get a ticket or get killed.
 

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That is badass about the JUN Supra. Also just to add a tidbit, I believe the Supra Turbo (with wing) has a CD of .35. That is due to the wider tires and wing. The NA has a CD of .33.
 

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mervinnn said:
That is badass about the JUN Supra. Also just to add a tidbit, I believe the Supra Turbo (with wing) has a CD of .35. That is due to the wider tires and wing. The NA has a CD of .33.
Then that is just proof of the massive high RPM power of the Supra. :cool: Imagine how fast the Supra would be on the highway with a Cd of 0.28!
 
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why said:
I think you are not using the correct equation to calculate top speed. Mass has small effect on top speed (on cars, not on boats), what counts is drag--aero drag specially. As far as I know, there is no relation between quadruple power to speed; a better relation is: power required is proportional to the square of speed.
Drag is proportional to the square of the velocity (v^2), but the
power requirement is proportional to the cube (^3) of the velocity. So to double the speed, you need eight times (8x) the power.

Drag = Cd * AirDens * Area * (v^2 / 2)
Power = Cd * AirDens * Area * (v^3 / 2)
 
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tony550m said:


Drag is proportional to the square of the velocity (v^2), but the
power requirement is proportional to the cube (^3) of the velocity. So to double the speed, you need eight times (8x) the power.

Drag = Cd * AirDens * Area * (v^2 / 2)
Power = Cd * AirDens * Area * (v^3 / 2)
Whoops.. yupe.. you got it right :)
Power=Force*Velocity... I guess I need to retake my basic physics class again.. LOL
 

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why said:


Whoops.. yupe.. you got it right :)
Power=Force*Velocity... I guess I need to retake my basic physics class again.. LOL
Are you at Purdue? I noticed you're in West Lafayette, the reason I'm asking is cuz I'm there too.

-Amir
 
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