200 Mph
ez = 1 + z + z2/2! + z3/3! + z4/4! + z5/5! + z6/6! + Torque ... ,
cos(z) = 1 - z2/2! + z4/4! - z6/6! + z8/8! - z10/10! + Horsepower ... ,
sin(z) = z - z3/3! + z5/5! - z7/7! + z9/9! - z11/11! + drag... .
All three series are valid for all real numbers. We want to accept the first one as valid for all complex numbers z. Then substitute z = xi, expand, use the facts that i2 = -1, i3 = -i, i4 = 1, and so on, and collect real and imaginary parts. You'll see that the real part of exi is just the series for cos(x), and the imaginary part is just the series for sin(x).
z = cos(x) + sin(x) i
and notice that when x = 0, z = 1. Then differentiate,
dz/dx = -sin(x) + cos(x) i
dz/dx = sin(x) i2 + cos(x) i
dz/dx = [cos(x) + sin(x) i]i
dz/dx = zi
(1/z)dz/dx = i
ln(z) = xi + C
for some constant C, by indefinite integration. Now use the fact that when x = 0, z = 1, to conclude that C = 0. Thus
ln(z) = xi
z = exi
exi = cos(x) + sin(x) i
|z| = sqrt(a2+b2)
z/|z| is then a complex number whose absolute value is 1. Then there is some t such that
cos(t) = a/sqrt(a2+b2)
sin(t) = b/sqrt(a2+b2)
tan(t) = b/a,
t = arctan(b/a)
You can always choose t in the range 0 <= t < 2 to satisfy these conditions. There are two t values in this range with tangent b/a, which differ by . Pick t > if and only if b < 0. Pick t = if and only if b = 0 and a < 0. Then
z = sqrt(a2+b2)[a/sqrt(a2+b2) + bi/sqrt(a2+b2)]
= sqrt(a2+b2)[cos(t) + sin(t) i]
= |z|eti
= eln|z|+ti
Required RWHP = Aerodrag RWHP + Rolling Resistance RWHP
Power = RWHP = force X velocity = (lbf)(ft/sec)/550
Aerodrag RWHP = (Cd)(A)(d)(V^3)/2/Gc/550
Cd = drag coefficient (unitless)
A = frontal area (ft^2)
d = air density (lbs/ft^3)
V = velocity (ft/sec)
Gc = gravitational constant (32.2 ft/sec^2)
550 (1 HP, mechanical = 550 ft-lbf/sec)
Rolling Resistance RWHP = (Cr)(W)(V)/550
Cr = rolling coefficient (unitless)
W = vehicle's weight (lbs)
V = velocity (ft/sec)
550 (1 HP, mechanical = 550 ft-lbf/sec)
Last edited by ZeeOSix; Dec 29, 2008 at 09:56 PM.
Last edited by ZeeOSix; Dec 28, 2008 at 12:14 AM.
Doing 200 MPH in a standing 1/4 mile vs. in a standing mile are entirely two different feats.
A 750 rwhp (~880 fwhp) car that weighs 3400 lbs with driver should hit ~145 - 150 MPH in a 1/4 mile. That means it only has to go 50 - 55 MPH faster in the next 3/4 mile. IMO, entirely possible. Doing a flying mile would make it even easier to do with that much power and the right gearing.
http://www.stealth316.com/2-calc-hp-et-mph.htm
http://www.autocalculator.org/Engine...alculator.aspx
Last edited by ZeeOSix; Dec 30, 2008 at 11:10 PM.
The Best of Corvette for Corvette Enthusiasts
For a top speed run, the differential should be changed to allow max HP usage from 5th gear.
A 3.42 rear end used in the spreadsheet gives ~205 in 5th gear at 6700 RPM. That's not a bad combo.
A Z06 tranny is actually setup worse for top end in 5th gear, as it's ratio is 0.84, and with a 3.42 rear end will only go ~173 MPH at 6500 RPM. In contrast, the 0.74 5th gear ratio gives ~199 MPH at 6500 RPM.
I haven't modded much of anything since the summer cam swap... I've just been swapping out worn out odds and ends (seat bottom leather and foam, broken drivers mirror glass, etc.) Nothing really exciting, heh. Your car looks like it's been coming together well.
Transmission Gear ratios
Gear LS1 / MN6 ....|.... LS6 / M12 6-speed
1st 2.66:1 ....|.... 2.97.1
2nd 1.78:1 ....|.... 2.07:1
3rd 1.30:1 ....|.... 1.43:1
4th 1.00:1 ....|.... 1.00:1
5th 0.74:1 ....|.... 0.84:1
6th 0.50:1 ....|.... 0.56:1
reverse 2.90:1 ....|.... 3.28:1
Last edited by ZeeOSix; Dec 31, 2008 at 02:02 AM.


Hey, genius, you keep on saying HP HP HP, and a lot of blah blah blah, but if you were really smart, you'd see that HP will not exist without torque. It's actually a transpose. So, in short, torque is the only measurement of power output from an engine. well, that and thermal output, anyway, but you don't transfer thermal loads directly into forward motion in most cases.
Anyway, think about this logically. If the formula that derives horsepower is directly dependent on the two variables of torque and rpm, then you will never have a change in horsepower without a change in torque or RPM. So when you say that horsepower is what matters in top speed, you are only correct insofar as you can't really not be correct. You can still be an idiot, though.
Top speed is dependent on torque, RPM's, and gearing. You can, of course, use the transpose formula for calculating horsepower and say the same thing in this manner: Top speed is dependent on horsepower and gearing. See the relationship? You are only wrong when you argue that it's not a matter of torque, but a matter of horsepower. If the RPM and gearing remain the same, it's a matter of torque, which increases the amount of horsepower.
So when you screamed "TOP SPEED is.... REAR WHEEL HORSE POWER, AERODYNAMIC DRAG + FRONT TIRE ROAD FRICTION + FRONT WHEEL BEARING FRICTION, AND GEARING" you could also have not been an idiot and said "TOP SPEED is.... REAR WHEEL TORQUE, ENGINE RPM, AERODYNAMIC DRAG + FRONT TIRE ROAD FRICTION + FRONT WHEEL BEARING FRICTION, AND GEARING"
Horsepower is a relational number, calculated from two other variables, the ones that matter. So stop being an idiot, and go read a book or something.
I learned all this on the back of a cereal box in Physics class, though...
1. Lower the car
2. Shave the mirrors
3. Tape off openings (but which openings??)
Should I an inch off the air dam to reduce the amount of air coming in under the hood to the radiator?
Any other suggestions
Also - I currently have a 273 with my 3-4 shift point set at 180. Is this the ideal gear for an A4 with this goal in mind? Or would a 315 or 342 be better. Thanks to all-
You ask about what to do with the front of the car. Best thing to do is make it a front breather and add a air dam to the front of the car. This sucks down to the ground at speed.
See the pic of my C4 Open Road racecar:

Then vent your hood:
I have not run the C5 to top speed yet, but my C4 has hit 206, but not from a standing start. Which I think is what you are attemting to do. I have right at 600rwhp in the C4, but I am loseing some top end with the wing. I need the wing though since I average 170 for 90 miles and make turns. If you do the front as described above you might find you need to have some kind of spioler on the rear to balance the downforce you have added to the front.
Jeffy'
Hey, genius, you keep on saying HP HP HP, and a lot of blah blah blah, but if you were really smart, you'd see that HP will not exist without torque. It's actually a transpose. So, in short, torque is the only measurement of power output from an engine. well, that and thermal output, anyway, but you don't transfer thermal loads directly into forward motion in most cases.

So exactly where did I say that HP wasn't a DERIVED unit of measurement? Can you really comprehend English? ... doesn't seem like it to me.
... are you Quasar's Dad? Dude, what do you think "torque, RPM" is ?? .... it's HORSEPOWER. Wow, I'm pretty sure you're really wrapped around the axle or higher than a kite on this stuff. Aren't you the retired GM engineer here? Wow.Horsepower is a relational number, calculated from two other variables, the ones that matter. So stop being an idiot, and go read a book or something.
I learned all this on the back of a cereal box in Physics class, though...
I think that cereal box had it all wrong ... or you just couldn't understand it. 
Aren't you glad you responded with your attacks claiming everyone is all wrong with your pompous BS that doesn't even make sense? Have a good one ... "genius".
PS -- Mr. Genius, please entertain and show me exactly how a car can go faster on top end at peak torque point than at peak HP point. I really want to see the proof.
Last edited by ZeeOSix; Dec 31, 2008 at 04:04 PM.
Last edited by ZeeOSix; Jan 1, 2009 at 02:32 PM.

So exactly where did I say that HP wasn't a DERIVED unit of measurement? Can you really comprehend English? ... doesn't seem like it to me.
Wow... are you frickin' sauced out? Who said torque and speed isn't related or doesn't define HP? Can you even understand what's being discussed here? And BTW, PEAK HP (along with gearing, aeros, etc, etc) is what determines a vehicles top speed ... NOT peak torque, as you say in the next sentence.
... are you Quasar's Dad? Dude, what do you think "torque, RPM" is ?? .... it's HORSEPOWER. Wow, I'm pretty sure you're really wrapped around the axle or higher than a kite on this stuff. Aren't you the retired GM engineer here? Wow.Psychobabble ... period. Isn’t that what I’ve been saying. What’s your problem? Listen carefully, torque and HP are related ... you know that, right? But it's ultimately HP that determines a vehicles top end speed. Period.
Ummm ... I think it's YOU that needs to re-educate yourself from when you tried to figure this stuff out back in 1959.
I think that cereal box had it all wrong ... or you just couldn't understand it. 
Aren't you glad you responded with your attacks claiming everyone is all wrong with your pompous BS that doesn't even make sense? Have a good one ... "genius".
PS -- Mr. Genius, please entertain and show me exactly how a car can go faster on top end at peak torque point than at peak HP point. I really want to see the proof.
http://www.bmwtuningmag.com/g-power-...isting-record/
PS ... for Mr. "Genius", my calculations show it takes ~ 640 rwhp to go 228 mph for a car like this. And I didn't even know how much torque this ccar makes. Ya know why? -- because torque at this point is unimportant if you know the HP. ONLY HP matters for top end. Use the equations in post #182 if you don't believe it. Go figure.
Last edited by ZeeOSix; Jan 3, 2009 at 01:33 AM.








