Frontal Area of F-bodies? *math*

[Rhode Island Red]

I've been curions for years on waht the top speed of F-bodies is taking into consideration of friction of our cars (0.32)

Using this Drag equation and This example

I thought it would be curious what an updated calulation table than http://www.f-body.org/gears/ would look like.

So does anyone know the frontal area of an F-body (In general) ?

[ConElite]

I know that there was a 93Z that was clocked in at over 210 with a average speed of 175mph+ in the "Silver State Challange." They can be serious speed demons.

With my gearing:
RPM 1st Gear 2nd Gear 3rd Gear 4th Gear 5th Gear 6th Gear
3000 27 40 55 72 97 144
4000 36 54 74 96 130 192
4500 41 61 83 108 146 216
5000 45 67 92 120 162 240

[Joe 1320]

Stock HP levels will push a car to approximately 157 mph, numerous tests have been published to back this up. It takes serious increases of HP to raise that speed due to drag.

[ConElite]

From what I heard, You need around 600hp to push the car past that and close to 200mph.

[Jeff_in_Atl]

As speed doubles air pressure quadruples.

[Rhode Island Red]

Stock HP levels will push a car to approximately 157 mph, numerous tests have been published to back this up. It takes serious increases of HP to raise that speed due to drag.

That is correct ! That is why I need the frontal area. I'm curious of the Force (Horsepower in this case) needed to exceed the drag force slowing down our car at 150+ . Using it in a table like above would give us owners an understanding why 6th gear is useless after 130 mph with 3.42's (rwhp output matches drag force) and what speed with 6th and 4.11's would the drag force match - neglecting the force created by tires-to-road drag force (need this # from the tire manufacturer or an expert on Tires *hint (wolfman)* )

It would be nice to have a table where you input your hp at an exact rpm (using your dyno table 3's) then you can figure out your actual top speed using any gear ratio or a master table for F-bodies the the hp # you need to exceed at an rpm (gear ratio would need to be inputted possibly). a six speed in 5th gear with a 2.73 gears would top out at 257 mph @ 6800 rpms which is totally ridiculous without taking account the fact that the drag force exceeds your rear wheel power output at plaid and ludicrous speeds (think spaceballs movie)

[Rhode Island Red]

Some #'s I've found for third gens using a google search

'88 Camaro IROC - Z:
Cd - 0.340
Area (m2 ) - 1.951
Area (ft2 ) - 21.00

'89 Camaro IROC - Z:
Cd - 0.340
Area (m2 ) - 1.973
Area (ft2 ) - 21.23

'89 Camaro IROC - Z Vert:
Cd - 0.420
Area (m2 ) - 1.973
Area (ft2 ) - 21.23

'92 Camaro Z28
Cd - 0.380
Area (m2 ) - 2.009
Area (ft2 ) - 21.62

'88 Firebird Trans AM GTA
Cd - 0.310
Area (m2 ) - 1.928
Area (ft2 ) - 20.75

I'm finding frontal areas between 21-24 sq-ft . low side for formula and high side for the TA's. Here is a nice table of info

[RangerBob]

Stock HP levels will push a car to approximately 157 mph, numerous tests have been published to back this up. It takes serious increases of HP to raise that speed due to drag.

I took mine to 155 in the desert in approximately 110 degrees F. It had more left, but I didn't. And it takes a LOOOOOOOOOOOOOOOOOONG time to stop at that speed!

This is with new tires, nitrogen filled.

[Wild Willy]

Yes, to run those speeds you want rock-hard skinny tires, just the opposite of what you would use for the best handling.

Seems like the easiest route to higher top speeds would be to reduce that drag on the top end- lowered, air dams, mirrors that folded in. The car is pretty slippery, and not that big of a hole to push through the atmosphere-

I have heard of several people who have been able to run around 160, plus or minus in a basically stock car. Some of them have been the police that used the B4C Camaros-

[Rhode Island Red]

I have figured out the Math needed to calculate closer to what the top speed of an F-body is taking accoun the drag at the higher speeds (ignoring road resistance due to tire contact - considerable at higher speeds)

Here is what you need

- Dyno graph or #'s of your dyno in your top speed gear (not 4th gear)
- The speed at a given RPM from your Dyno run .


Using

Drag of 1995 TA (0.34)
Density of air at sea level at regular air temp 0.076474203 lbs/ft^3
Frontal Area of 1995 TA 22 ft^2
The Top Speed = Speed at RPM - Speed reduced by drag
The 0.01136 is 60/5280 to convert to MPH
The .57 is the Pressure, Area, drag multiplied and simplfied

Simplifying things out
Actual speed - speed on Dyno at RPM - Speed lost due to drag

So
Top speed (F-bodies) = Speed at RPM - [sqrt((2*D)/(0.57))*0.01136]
)

D = the Torque at the specific RPM

Best one can do without the 2 graphs from a dyno for a given Gear

So you'd need the 2 graphs of 6th gear to unserstand why the top speed is so low for 6th - just not enough torque to overcome Drag caused by air