i have two questions, how much does weight affect 1/4 mile times, i mean like whats the equation, ive heard that every 100lbs lighter= 1 tenth faster, is this true? and how many car lengths difference would there be between say a 14.9 and a 14.0, i've also heard every car lentgh is a tenth but this seems like too much.
1/4 mile times?
- Thread starter 1993cobra
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It is hard to say how weight will effect your times without knowing what kind or rwhp you are making. Power to weight is everything.
Every car length is NOT a tenth... That would be a full second, roughly.
There's also the old saying: The fastest way to take 100 lbs. out of your race car is to find 1600 places to take an ounce... (think that's how it was, lol).
Losing weight is like gaining hp... less weight to try and propel. It also helps your brakes out by lightening the load. 100lb's less has the potential to yeild a full tenth in the 1/4, but there's so many other variables that it can be hard to prove.
There's also the old saying: The fastest way to take 100 lbs. out of your race car is to find 1600 places to take an ounce... (think that's how it was, lol).
Losing weight is like gaining hp... less weight to try and propel. It also helps your brakes out by lightening the load. 100lb's less has the potential to yeild a full tenth in the 1/4, but there's so many other variables that it can be hard to prove.
Unfortunately neither of your questions can really be answered. As the others have posted, the effect of weight reduction will depend on many factors and can't be boiled down to a simple formula.
As for translating ET differences to car lengths, that depends on the terminal speed of both cars. If each was traveling at 125 mph, the distance between the cars in your example would be 165 feet, or roughly 9 car lengths.
As for translating ET differences to car lengths, that depends on the terminal speed of both cars. If each was traveling at 125 mph, the distance between the cars in your example would be 165 feet, or roughly 9 car lengths.
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Ok lets get technical. Weight is a given, of course thats gonna make it faster. but as for a tenth being equal to a car length, that is a fact. A FULL SECOND!!!??? have you ever been beside a car at the track a full second faster than you. well unfortunately i have and it was a LOT more than a car length difference. but anyway, back to the subject, i know a tenth is worth a car length and i can prove it here. ready, here it goes. 1/4 mile=1,320ft. say your car ran a 14.0. that would mean roughly that your car is going on average 94' 1/4" a second. now, if your car runs 13.90's, that would put it right at 95 ft a second, roughly 3/4 of an inch more per second than a 14.0 PLUS with it leaving a whole tenth left over with the difference in 13.90's and 14.0's the difference would be right at 10 1/2" plus the extra 9.4 ft for the extra tenth putting it right at 10 1/2 to 11 ft difference at the end of the 1/4 mile. whew, there. and with the stock length of the cobra being 183.5" would put it at 15' 3 1/2" would leave only close to a 1/4 of a car to spare on winning by a whole car length difference. there, thats the facts. then you have reaction time, shifting, all those goodies to look at too but for basic facts, that sums up that a tenth is equal to approx. 1 car length.
The only thing I agree with here is that removing weight will make you faster.
A tenth is NOT worth a car length. Like was mentioned in other posts there are way to many variables for that be. (Torque, hp, shifting)
I have an example.....A friend of mine has a 96 cobra. He and I usually play together when we go to the track to practice. On average when I run him normally aspirated he is 2/10-3/10 faster than me. Now for the kicker of it, the most that I can recall him beating me by is 1 car length. That's right not 2 or 3 car lengths.
So according to your formula 1 second difference is equal to 10 car lengths. I too have been beside cars 1 second faster than me and 1 second slower than me and have never beaten or been beaten by 10 car lengths.
That should clear some things up to start, but... Try this idea... 55mph is 88' per second. Is your car 88' or longer? Uh uh.. Your car is about 16' long. So, at just 55mph, it's moving about 5.5 lengths per second. If you can trap speed at 110mph, you're moving at the rate of about 1 length per 1/10th of a second.
If my math is wrong, so is what I just said!
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