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Here he is with a bike behind him. I can't tell for sure if he has a spoiler or not. He has some other videos during the day which should tell us.

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I've looked at 3 videos and I can't tell for certain in any of them. I can't see any photos he posted anymore to tell either. For sure he was either running no spoiler or stock. I think he has a 2007 GXP and I can't remember if the spoiler was standard on an 07 GXP or an option.

It was after he had the "Oh Chit my entire rear end felt like it was going to come off the ground" that he added a spoiler. Not sure he kept it on though because it was obnoxious.
 

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Discussion Starter #62
Ye I have already but you gave an idea. ?

Crazy yes stupid no haha I'm sure it wouldn't work but I have a couple of those cast Sky's I could play with but there is no top so I'd have to make one. I'm sure it wouldn't work but worth a try. Those are so small I could make a wind tunnel for it myself ?

He added the spoiler after that run. Not before. Since you have me curious, I'm going to pull his run with the bike to see if he had a stock spoiler or none.

Try a local university for a wind tunnel. You have the background. You could make models and see if they'll give you some time or even see if you can get a group of enginerding students to work with you part of their design project class. My university had a wind tunnel.

Give me a few minutes and I'll find some video of the car.
 

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No turbo here don't want one plus everybody runs a turbo. The new SC is just for the extra CFMs viruses the 62. I plan to do some motor work as we'll. DDM Dave is thinking a LSJ head and custom ground cams. Once I get my new T56 trany I'll be heading up to their shop for some work. ?
Perhaps Dave @ DDM will knock some sense into you when you tell him your lofty goal and show him that tiny supercharger. Perhaps you'll add a 400 shot of nitrous that we don't know about?
 

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Discussion Starter #64
Dave knows about it and has some ideas :)

He knows I want to stay with a SC system although I'll be going with bigger tubes, big bore throttle body then maybe a LSJ head and custom ground cams and who knows what else. :)

Perhaps Dave @ DDM will knock some sense into you when you tell him your lofty goal and show him that tiny supercharger. Perhaps you'll add a 400 shot of nitrous that we don't know about?
 

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I believe by "stock", they mean stock hardware with no RPM limit (or a raised RPM limit). The 192 was reportedly hit at ~6900 RPM...which pretty much matches what you would expect with the stock ratios.

And in a theoretical context, using a 233HP (at the wheels) 150mph baseline, it would take 482HP to get to 192. And 544HP to get to 200. These are theoretical extrapolations of the 233/150 assumption. Of particular qualitative value, note how much additonal HP is required to squeak from 192 to 200 (a mere 8 mph more)...takes an additional 62HP!

Also, those are "at the wheels", so the engine itself is putting out 500+ at 192 and "would be" pushing 600 at 200. Again, extrapolation from baseline assumptions.
just like the bugatti only needs 250hp to reach 150mph but needs and additional 750hp to reach 250mph!
 

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I thought torque played a bigger roll in getting you going and horsepower sustains your acceleration.
That statement is a simplification to help distinguish the difference in layman's terms.

The physical reality is torque does it ALL. Torque is the force. Star Wars analogies notwithstanding, "Force" makes you go whether it's getting started or keeping you going.

Power is a "measure" of the rate of work. And work is force through distance. So power is a measure of the rate of force through a distance. Given the same torque, more power is realized/required the faster you move (or rotate, as the case may be).

Or, more succinctly, to increase or sustain speed (in the automotive sense) against drag and friction...you must maintain an ever increasing torque...and that takes an ever increasing amount of power.

Also, in the automotive world we can take advantage of torque amplification via gearing...where we realize at the wheels a much higher torque at lower speed (short gearing) and then trade torque for speed (as the gears go up)....all the while delivering roughly the same amount of power.

So the simple statement: "torque plays a bigger role in getting you going and horsepower sustains your acceleration" is OK. Because you can gear in tremendous torque at the low end (to get you going)....but you ultimately need power to sustain the torque needed to keep you going on the high end.
 

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Took the words right out of my mouth, Bogie!!:yesnod:
 

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Well, one thing is for certain...I need more than my little 2.4 can deliver. I only made 88 mph at the drag strip last night. A little boost might help. :dunno:

Only 112 more to go to 200 mph!! ;)
 

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That statement is a simplification to help distinguish the difference in layman's terms.

The physical reality is torque does it ALL. Torque is the force. Star Wars analogies notwithstanding, "Force" makes you go whether it's getting started or keeping you going.

Power is a "measure" of the rate of work. And work is force through distance. So power is a measure of the rate of force through a distance. Given the same torque, more power is realized/required the faster you move (or rotate, as the case may be).

Or, more succinctly, to increase or sustain speed (in the automotive sense) against drag and friction...you must maintain an ever increasing torque...and that takes an ever increasing amount of power.

Also, in the automotive world we can take advantage of torque amplification via gearing...where we realize at the wheels a much higher torque at lower speed (short gearing) and then trade torque for speed (as the gears go up)....all the while delivering roughly the same amount of power.

So the simple statement: "torque plays a bigger role in getting you going and horsepower sustains your acceleration" is OK. Because you can gear in tremendous torque at the low end (to get you going)....but you ultimately need power to sustain the torque needed to keep you going on the high end.

THank you good Sir for clarifying. :cheers:
 

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There are a couple calculators that I have seen that give rough calculations for how much power is needed for certain speeds.

The calculation that I have used and seems pretty accurate is -

Power required = 8.702 x 10**(-6) x Cd x A x V**3

where Cd = coefficient of drag (look it up for your vehicle)

A = square feet of frontal area of the vehicle

V = Velocity, in miles per hour


So a working example for a stock 2.4L - with 130mph top speed

Required Power = (8.702 x 10**(-6) x.44 x 21.1 x 130**3

Required Power = 0.000008702 x .44 x 21.1 x 2197000

Required Power = 177.49

Which matches up to what a stock 2.4L can do on a long road pretty closely in stock trim and stock power.


A Stock 2.0L with a tune making around 300hp at the wheels ( around 350 crank) can do roughly 164mph.

Required Power = (8.702 x 10**(-6) x.44 x 21.1 x 164**3

Required Power = 0.000008702 x .44 x 21.1 x 4492125

Required Power = 356.35


Of course this is just a rough estimate, there are other factors that need to be considered also like gearing, etc that will make a difference, but this seems to give a pretty close estimate of needed power for a certain speed.


So if we look at what it would take to achieve 200mph, it looks like this -

Required Power = (8.702 x 10**(-6) x.44 x 21.1 x 200**3

Required Power = 0.000008702 x .44 x 21.1 x 8000000

Required Power = 646.31
 

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Come on Dave, don't ruin Rickys dream ......












Yet...
 

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Discussion Starter #73
Thanks But he isn't :)

The Lamborghini Aventador has a CD of .23 but a frontal area of 25.079 ft. It also has 701HP but only 507lbs of torque. Now we know by these calculations and knowing torque gets you down the road it would take only 536HP to go it's top speed of 220 but it would need pretty close to that same torque to get there. which it's 29lbs short but it will go 220. Like Dave said these are numbers in theory and frontal area is one thing but the way the air hits it is another. Not sure how much can be done to reduce the frontal area of our cars but I can do things that effect the overall drag. Under body panels, ground effects and a hardtop slopped back window could have a great effect especially the top and back window. Like any project I have to build the car the way I am going to. See what I get then go from there. :)
 

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what about if you get close? would that be good enough? I mean you said you had it going to 15something as I recall and that was not fast enough. Is the goal is to hit 200 and then pull back? or 200 and keep going?
 

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Discussion Starter #75 (Edited)
Nope 200 is the mark.

Once I hit that I'll be done. I just want to prove that you could have bought a Sky new for 30k and stick another 10, ok maybe 15 and get it to go 200 instead of buying a 100+K car. Just something I want to do. To take a small GM roadster with a 4 cylinder and actually go 200MPH would be something don't you think?
A major underdog:)

what about if you get close? would that be good enough? I mean you said you had it going to 15something as I recall and that was not fast enough. Is the goal is to hit 200 and then pull back? or 200 and keep going?
 

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Once I hit that I'll be done. I just want to prove that you could have bought a Sky new for 30k and stick another 10, ok maybe 15 and get it to go 200 instead of buying a 100+K car. Just something I want to do. To take a small GM roadster with a 4 cylinder and actually go 200MPH would be something don't you think?
A major underdog
:)
Indeed, all I care about your survival man, dieing to go 200 is foolish perhaps in this car that was NOT designed to go 200 is all... good luck on your venture..:thumbs:
 

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Discussion Starter #77 (Edited)
Yes I agree :)

Indeed, all I care about your survival man, dieing to go 200 is foolish perhaps in this car that was NOT designed to go 200 is all... good luck on your venture..:thumbs:
Thanks for your concern Buddy.
We have all done things that are foolish and your right this car was not built to go 200 that's why I only want to do it once or maybe 3 times:) I'm not planning on going that fast on a regular basis that would be crazy :lol::lol:
Trust me I will be doing runs to see how it reacts at 160, 170,180 and so on until I know it's going to be stable at speed as well as letting off. If things get bad I'll let off tell I figure out why. I may be crazy but I'm not stupid :)
 

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The Lamborghini Aventador has a CD of .23 but a frontal area of 25.079 ft. It also has 701HP but only 507lbs of torque.
In terms of top end drag, torque off the engine is relatively moot. The key is power and gearing. Because if you have adequate power, you can gear it to deliver true torque needed at the wheels. On the flip side, simply having high torque isn't enough. You need high torque AND the ability to move that torque in space and time.

The Aventador can get away with 507 lb-ft off the engine because it has the power (made possible via it's 8000+ RPM), which enables it to have shorter gearing while still delivering the speed and torque needed to achieve top speed.

At the end of the day, it's how much torque is actually applied to turn the wheels and the ability to generate that torque at a fast enough rotation rate to achieve top speed. The rate at which torque is delivered is POWER.
 

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Discussion Starter #79
Very true

I wasn't trying to compare my car to the Lambo just some interesting numbers :)
That's why I'm going to the T56, I need that extra gear.

In terms of top end drag, torque off the engine is relatively moot. The key is power and gearing. Because if you have adequate power, you can gear it to deliver true torque needed at the wheels. On the flip side, simply having high torque isn't enough. You need high torque AND the ability to move that torque in space and time.

The Aventador can get away with 507 lb-ft off the engine because it has the power (made possible via it's 8000+ RPM), which enables it to have shorter gearing while still delivering the speed and torque needed to achieve top speed.

At the end of the day, it's how much torque is actually applied to turn the wheels and the ability to generate that torque at a fast enough rotation rate to achieve top speed. The rate at which torque is delivered is POWER.
 

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There are a couple calculators that I have seen that give rough calculations for how much power is needed for certain speeds.

The calculation that I have used and seems pretty accurate is -

Power required = 8.702 x 10**(-6) x Cd x A x V**3

where Cd = coefficient of drag (look it up for your vehicle)

A = square feet of frontal area of the vehicle

V = Velocity, in miles per hour


So a working example for a stock 2.4L - with 130mph top speed

Required Power = (8.702 x 10**(-6) x.44 x 21.1 x 130**3

Required Power = 0.000008702 x .44 x 21.1 x 2197000

Required Power = 177.49

Which matches up to what a stock 2.4L can do on a long road pretty closely in stock trim and stock power.


A Stock 2.0L with a tune making around 300hp at the wheels ( around 350 crank) can do roughly 164mph.

Required Power = (8.702 x 10**(-6) x.44 x 21.1 x 164**3

Required Power = 0.000008702 x .44 x 21.1 x 4492125

Required Power = 356.35


Of course this is just a rough estimate, there are other factors that need to be considered also like gearing, etc that will make a difference, but this seems to give a pretty close estimate of needed power for a certain speed.


So if we look at what it would take to achieve 200mph, it looks like this -

Required Power = (8.702 x 10**(-6) x.44 x 21.1 x 200**3

Required Power = 0.000008702 x .44 x 21.1 x 8000000

Required Power = 646.31
The bolded equations are missing a parenthesis somewhere so just to clarify I am assuming,

(8.702 x 10**(-6) x.44 x 21.1 x 200**3

Should read:

(8.702 x 10**(-6)) x.44 x 21.1 x 200**3

Based on the follow on information where 8.702 x 10**(-6) has been simplified as 0.000008702

Thanks for this Dave...love it when I can do the math.

(Also, I believe the V**3 for the stock 2.0 RL should be 165 not 164 as the cubed root of 4492125 is 165...just checked it to make sure I had the formula right for this next part.)

Using Dave's math, (and assuming I have Dave's equasion right...I am a History major for god sakes!) if Ricky can see a 10% aerodynamic improvement in CD with the hard top (Dropping the CD to 0.396) then by using Dave's formula we can see the required power to reach 200 mph would drop to 581.68 hp. A 15% improvement in CD drops the required power to 549.37, almost 100 hp less. And with a 20% improvement (a CD of .35) power required drops to 517.05.

What's interesting to note Ricky is that once you have the top on and make a dyno run then do a top speed run you'll be able to calculate what the new CD is base on the above formula as well. Great tool you shared with us Dave!
 
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