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Author Topic:   weight loss = HP?
strobe
Dirt Roller

Total posts: 23
posted November 01, 2004 12:13 PM  
Somebody once told me that for every 100 lbs you strip off your car, you gain 20 HP? . Anyone know any more on this? I would think you might gain a little, but not 20 HP.

[This message has been edited by True Blue (edited November 01, 2004).]

supwitchew
Dirt Maniac

Total posts: 122
posted November 01, 2004 02:25 PM  
You don't gain any horsepower by reducing the weight of the car. It just feels like it because you will accelerate quicker. As the mass decreases, acceleration will increase. Newton's second law.
Acceleration = Force/Mass

Hope this helps.

racer17j
Dirt Forum Champ
Total posts: 5390
posted November 01, 2004 05:29 PM  
WoW what have I been missing

iowatoolman
Dirt Freak

Total posts: 369
posted November 02, 2004 12:34 PM  
don't foregt that flames add another 15-20

;-)

drive hard or drive home

strobe
Dirt Roller

Total posts: 23
posted November 02, 2004 12:51 PM  
Geez, thanks guys. I guess it's my own fault. i should have worded the original question something like "Losing 100 lbs of weight is the equivalent of gaining 20 HP." But I assume nobody has ever heard of such a thing, therefore I'll retire to my little hole with my dunce cap.

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Dirt track racing, cuz golf and baseball only require one ball.

supwitchew
Dirt Maniac

Total posts: 122
posted November 02, 2004 01:36 PM  
You have to remember that it would be directly proportional to how much the car weighed initially. Loosing a 100 pounds off of a 2500 pound car would be more significant than loosing 100 pounds off of a 4000 pound car given that the motor and drive train were identical. Also, you should wear your dunce cap proudly. I do.

supwitchew
Dirt Maniac

Total posts: 122
posted November 02, 2004 01:41 PM  
Also, you can add another 20-30 hp by placing stickers like NOS, Wilwood, Turbo Blue, etc. in strategic places. The "I Love Hooters" bumper sticker is an automatic 40 hp gain. Most racers don't know that.

racenmotorsports
Dirt Maniac

Total posts: 169
posted November 02, 2004 07:03 PM  
Hey thanks Sup...didn't know the Hooter sticker trick. I'll try it LOL!!

19J
Dirt Freak

Total posts: 370
posted November 03, 2004 07:46 AM  
Actually to an extent that could be true. There is 2 diff ways to rate hp. At the flywheel/crank(most dynos) or at the rear wheels. The less weight and less friction you have through the drive train the more rw hp you will have. I dont know about 20 but i bet you will get some. Ive been told and i wish i remembered this exact. But i want to say it takes 1 hp to move 4lbs 1 foot? in a sec? Its close to that. So less weight the less power it takes to move the car. Your motor wont gain any hp you just might "free up" some power at the rw. JMO

redneck racing
Dirt Forum Champ
Total posts: 860
posted November 05, 2004 10:12 PM  
Ive heard that you can gain up to 12hp without the use of power steering and an alternator. Eddie

strobe
Dirt Roller

Total posts: 23
posted November 07, 2004 08:25 PM  
The O.D.M.(owner, driver and mechanic) for the car said that it takes around 7hp to run the alt. and there's a rod in the steering linkage that you can shorten up. So you don't have to run a steering pump. By shortening this rod, it takes less manual effort to turn the wheel. Next season doesn't start for another 6 months anyways. Lots of time to tinker around.

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Dirt track racing, cuz golf and baseball only require one ball.

jammin
Dirt Administrator

Total posts: 6243
posted November 07, 2004 08:42 PM  
Jammin, the car weighs around 3450 right now with full tank of gas and driver. the driver says she handles the track(4/10 banked) like it's on rails. and now he's talking about putting a 400 sbc in her. I was never really gonna take weight of the car in the first place(3200 lbs minimum) cuz like I said, she handles like a dream. Nobody else I know runs a 400 in our class(200 lap Enduros). He's very anxious to run the 400, but I don't know. There must be a reason that nobody runs a 400...?

jammin
Dirt Administrator

Total posts: 6243
posted November 07, 2004 09:24 PM  
where are u running 200 lap endoros at

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dirt is for racing asphalt is to get there

strobe
Dirt Roller

Total posts: 23
posted November 08, 2004 06:47 AM  
quote:
Originally posted by jammin:
More than likely, you would be ok in that class to do it.....The car is heavy enough, it should be fine.

jam


The same guy that told me about the extra 20hp stuff also told me that the 400 sbc likes to run hot. That's why I'm kinda iffy on running a 400. But we do have a 2 core aluminum racing rad in the car.

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Dirt track racing, cuz golf and baseball only require one ball.

strobe
Dirt Roller

Total posts: 23
posted November 08, 2004 07:05 AM  
quote:
Originally posted by dirtracing76:
where are u running 200 lap endoros at


Winnipeg, Manitoba, Canada www.victorylane.mb.ca

We only race 5 times a year. One saturday a month from May to September. $1000(Canadian) to win. Usually 40 cars in the race.

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Dirt track racing, cuz golf and baseball only require one ball.

Dmac
Dirt Roller

Total posts: 23
posted November 08, 2004 08:16 PM  
I heard they are going to 7 Enduro's for the 2005 season Strobe.

Mikey14
Dirt Freak

Total posts: 265
posted November 10, 2004 02:22 PM  
old drag racing days it was always rumored that if you could shave 100 pounds then assuming all other things are equal you've shaved a tenth off your quarter mile time.

This is also effected by the law of deminishing returns though. the more you lose, the less gain you'll see percentage wise.

shifter
Dirt Roller

Total posts: 16
posted December 04, 2004 09:59 PM  
I can tell one thing I learned in drag racing. For every 100 lbs. you can take from the car, you'll gain a tenth of a second, or for every 10 lbs., you'll gain a hundreth of a second. If that helps any at all.

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