True or False: As power increases, weight reduction means MORE?
08-07-2004, 01:45 AM
#1
Banned
Thread Starter
iTrader: (7)
Join Date: Jun 2003
Posts: 559
Likes: 0
Received 0 Likes
on
0 Posts
True or False: As power increases, weight reduction means MORE? Here is my reasoning.
Take a stock F-Body:
Approx 3500 lbs with driver.
Approx 350 flywheel horsepower.
10 lbs to every 1 horsepower.
Approx 10 hp to drop .1 in the ¼.
3500:360 = 9.72:1
9.72:1 = 3402:350
At that point, dropping 98 lbs is the equivalent of a gain of 10 bhp.
Now add heads/cam/nitrous to the same car:
3500 lbs
600 bhp
5.83 lbs to every 1 bhp.
3500:610 = 5.74:1
5.74:1 = 3444:600
Now dropping only 66 lbs is the equivalent of a gain of 10 bhp
Please feel free to critique my reasoning. After all, it is a question, not a claim.
Take a stock F-Body:
Approx 3500 lbs with driver.
Approx 350 flywheel horsepower.
10 lbs to every 1 horsepower.
Approx 10 hp to drop .1 in the ¼.
3500:360 = 9.72:1
9.72:1 = 3402:350
At that point, dropping 98 lbs is the equivalent of a gain of 10 bhp.
Now add heads/cam/nitrous to the same car:
3500 lbs
600 bhp
5.83 lbs to every 1 bhp.
3500:610 = 5.74:1
5.74:1 = 3444:600
Now dropping only 66 lbs is the equivalent of a gain of 10 bhp
Please feel free to critique my reasoning. After all, it is a question, not a claim.
08-07-2004, 02:20 AM
#2
TECH Apprentice
iTrader: (13)
Join Date: Jul 2003
Location: Tempe, AZ
Posts: 357
Likes: 0
Received 0 Likes
on
0 Posts
I would agree, also as your car gets lighter weight reduction starts to count even more. removing 100 lbs off a car that only weighs 3000 lbs is more effective than removing 100 lbs off a 3500 lb car.
It takes 4X the power to accelerate a 4000 lb car the same speed as a 2000 lb car. for every time you double the weight you need 4 times the power to keep it accelerating at the same speed. somthing like that I learned in math class, I hope that made sence because I am very tired.
It takes 4X the power to accelerate a 4000 lb car the same speed as a 2000 lb car. for every time you double the weight you need 4 times the power to keep it accelerating at the same speed. somthing like that I learned in math class, I hope that made sence because I am very tired.
08-07-2004, 07:33 AM
#3
Banned
Join Date: Sep 2002
Location: So Cal, CA
Posts: 1,298
Likes: 0
Received 0 Likes
on
0 Posts
When you think about a street bike at 400 lbs.
If you add 50 horsepower to a street bike itll pick up the kind of gains 150-200 hp will on a car....so yes...weight means more.......
If a car has 1000hp, 100 lbs will benefit alot equal to a bunch of hp gain
If you add 50 horsepower to a street bike itll pick up the kind of gains 150-200 hp will on a car....so yes...weight means more.......
If a car has 1000hp, 100 lbs will benefit alot equal to a bunch of hp gain
08-07-2004, 10:25 AM
#4
TECH Fanatic
iTrader: (2)
Join Date: Jan 2004
Location: Ewing, NJ
Posts: 1,222
Likes: 0
Received 0 Likes
on
0 Posts
weight is always important! hehe
but a weaker engined car will get more gain from it than a high power car. when i bracket raced my little 84 cavy i went with teh car all stock and everything in it and it ran 19.9's. next time i went the weather was about the same and the car ran 19.6's. teh only difference was the jack and spare and a few other loose things in teh car had been removed. prolly not even 100lbs of stuff accounted for nearly 3tenths and 2mph of trap speed.
either way, to generate trap speed you are going for a better power to weight ration. work on whichever side of the ratio you can afford and you will make gains :burnout:
later
tim
but a weaker engined car will get more gain from it than a high power car. when i bracket raced my little 84 cavy i went with teh car all stock and everything in it and it ran 19.9's. next time i went the weather was about the same and the car ran 19.6's. teh only difference was the jack and spare and a few other loose things in teh car had been removed. prolly not even 100lbs of stuff accounted for nearly 3tenths and 2mph of trap speed.
either way, to generate trap speed you are going for a better power to weight ration. work on whichever side of the ratio you can afford and you will make gains :burnout:
later
tim
08-07-2004, 11:43 AM
#5
TECH Senior Member
With a slow heavy car (say mid 14s and 4000 lb raceweight) I'll take the 10 HP over the 100 lbs dropped for sure. But on an 8 second car weighing 2800 lbs I'll take the 100 lbs over the 10 hp by a looooooooong shot! The quicker you go and the lighter you get, the more weight reduction matters comparative to HP.
