First, Main Question: Given really soft racing tires and infinite HP, what is the '94 Formula’s top speed on flat pavement? At what point would the front end start coming up too much to be driveable? Is the car aerodynamic enough to actually start peeling out before flipping up or getting squirrely (I doubt it)? Would it help to put ground effects on it?
My brother got this car up to redline in 5th gear @ 5,750RPM’s, with room to go. Now, theoretically that is 189.75 mph (assuming the speedo is correct at 33mph in 5th gear at 1,000 RPM’s). But, I know this cannot be possible because he does not have enough HP to be able to do this and the shape of the car I would assume is not able either (or maybe he had the wind with him??). He has small mods such as cat-back flows, cold-air intake, a chip.
Second Question: Anyways, he is gonna buy a kit for $3,500 to supercharge this beast. The car ran a 13.8 with us as amatuer drivers. So, we figure it’s best speed is 13.5 which would be about 320 HP, correct? So, what would be his HP and top speed after the charge???
youre right, a 4th gen LT1 will not pull 189.75mph… a few questions… what gears are in the rear and are they stock? also, what tire/wheel combination is on the car and is it stock too?
well, if all you cared about is top speed in a straight line… you dont want wide tires… you want as skinny as you can get away with because tires are a huge part of drag with all the turbulence they create and at high speeds i read that they kind of compress the air as they roll over the ground… keep in mind if youre gonna be doing this often you need to make sure you have tires that are up to the job… pop a tire at 150+ and you are going to die.
you should get the car lowered some… that will help if you want to go top speed, but lowering usually involves sacrificing ride quality and launching ability at the track… so you need to figure out the tradeoff’s
and what do you mean by peeling out… like the back tires spinning faster than the car can go at 150+ mph? no… your car will never do that, it just wont accelerate anymore… your car will probably never flip over like a nascar and those mercedes le mans’ cars do… remember those cars are pretty light compared to yours… in any case you would probably get scared once the nose started to lift some because the steering responds less and less…
i read a R&T road test of stock sports cars awhile back and an lt1 camaro ran 155mph or so stock, so maybe yours did 160…
it would probably go 200mph easy in a STRAIGHT line… given the right amount of power… but to do it safely would require a ton of modifications…
When I bought one in '93 (first year of that body style) the dealer literature talked about a private team speed testing Formulas on salt flats. The only thing that was stock was the body, and if I remember correctly the top speeds were close to 300.
I would say that he could not attain this speed unless he were on a high-banked long oval track. And then I would not believe it. There just is not enough horse power in the stock engine.
Question the second,
We need specs on the blower to be able to even estimate the horsepower output. You can usually chop a second off your times with a blower added. So 12.5, maybe. If you can get it to hook up that is (minimize wheel spin).
The first question was with infinite HP, whuckfistle.
bsane, there is no way the car of that shape could reach 300, sorry.
something clever, lowering the car is not an option, but ground effects is an option. Not sure if that would help… it would be a tradeoff between more drag and less lift.
low pro tires with 17" wheels. Rear end has not been touched, to our knowledge. FYI, first gear goes to 45mph. Is that stock?
** Anyone know the coefficient of drag of the '94 Formula??** I’ll look for this spec.
I can’t get in touch with my bro to ask about the blower specs. Later maybe.
Bsane, is that a stock body? I am not an expert, but everything I have known about cars tells me that that is not possible. There is not enough downforce being applied, I would think… No spoiler, not low enough, ect.
The 1996 Firebird Formula had a drag coefficient of 0.34 (for reference, a 2003 Honda Accord sedan has a Cd of 0.29), which suggests that it’s top-end is no-where near 190 MPH, even at 300 HP. The cite above gives a quarter-mile time of 14.4 seconds, so I presume the car you were driving must have been significantly upgraded to shave nearly a second off of stock.
I’m showing that this vehicle has a .34 coefficient of drag.
My source, a most unimpressive one, is CarTest, the computer program.
Incidentally, CarTest shows a stock '94 Formula turning a 14.9 at 94.7 in the quarter.
Does this car actually weigh 3720?
well, there is More to top speed than CD. More important is frontal area and downforce matters too.
I already mentioned what has been done to the car, it definately did a 13.8. It beats or keeps up with every corvette we race and we beat a 350z to 120 by 2 car-lengths. We are not sure what all has been done to it because we just bought it a few months ago. It cooks.
Our car weighs 3400 and change according to epinions.com
Right. Sometimes you get strange differences based on options, and some weights carmakers give include oil, gas, coolant, etc while others don’t.
And of course you have to calculate the weight of the driver in with all this…
By the way, at 190 this vehicle would suck up 340 HP just in aerodynamic losses. Transmission and tires will also suck up some horsepower.
Your brother may have gotten this vehicle to 5000 RPM in 5th gear, but perhaps he did it on a slight downhill grade and did not notice the slight downhill grade in question?
I could imagine it happenning to me, if I owned a bitchin’ Firebird.
I ran your numbers in CarTest, except I dropped car weight to 3400, added 265/50ZR17 tires, then added 10% to horsepower and torque. I then added 10% again and again and again.
Here’s the weird part… right around 432 HP and 505 ft-lb of torque, the car turns a 12.7 quarter, but has a top speed of 180.
Great. Thanks jonathan woodall. I’ll check that cartest thing out myself. The only thing is that it’s theoretical, I was looking for people who have actually maxed out a supercharged firebird with the same body. I’m sure there is someone on this board who has done this!
Yeah, CarTest is awesome, but “Garbage In, Garbage Out”. If you feed it your car’s data, you’ll get your car’s real results to a high degree of accuracy.
Since you guys appear to not know how the car is modified, etc, and probably don’t have it dynoed, etc, it’d be hard to make accurate predictions.
Hint: the DOS version is shareware, but the Windows/JAVA version is crippled beyond usefulness… which sucks, 'cuz it’s way pretty.
btw i have seen pics of that 298mph firebird and it is lowered and has special suspension and the tires are rather skinny up front like i was talking about… at the time i saw it i believe it was RED with a bunch of graphics…
If you already got it to 5000 rpm in fifth, you could modify the engine until the cows come home and about all you’ll accomplish is more power and acceleration.
Until more power is added along with some gear changes, you won’t really be in the business of more top speed.
That pushrod motor can be pushed, but not much above the 5,000 rpms (enter some people who will refute this, but c’mon…how much top speed can be gained)
Fuel, if he was close to redline in fifth, how fast do you think you could go if you squeezed out a few hundred more RPMs? At this point, you are limited by a (relatively) short gear. If the motor has the balls, you need a longer final drive …a taller gear…a rear gear that is lower numerically…which ultimately slows acceleration in favor of top speed.
The motor is ok at redline…that isn’t the point. The point is that redline’s topspeed doesn’t change no matter how much motor you’ve got. You MUST adress the gears, or top speed convos are meaningless.
Take a car that redlines in top gear and it does 125.
Double the horsepower and top speed should still be 125 at redline.
Unless some attention is paid to the final drive ratio, you won’t see benefits to top speed from horsepower.
Back when they were a real magazine, Car & Driver had a project Firebird (IIRC it was a '94) that they planned to do 200mph with. You need something like 300 hp more to do 190 than to do 180; I think they got Reeves Calloway to build the engine for them, something like 700hp or so. IIRC they got to 203 mph.
They did the same thing at Bonneville a few years later, and the driver said at about 175 the car felt “weird”. The mechanic bolted something like 400 lbs. to his bumper, and told him to “drive through it”. At around 185 or so, the car launched itself into the air & flipped around, sliding for something like a mile on its roof. The driver was ok, but I think they ended the project there.
This is all being dredged up by my mushy memory, though I also remember a cd of .34 for the '94 Firebird, so maybe I’m not that off. But I know for certain that a '94 Firebird has gone over 200.