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Discussion Starter #1
i just did some math and it seems that for every 100 lbs you loose on your focus, you gain almost 10hp as an equivalent. So loose 10 lbs and get 1 hp is the rough equation.

So if you tear out your rear seats, put some ligher race buckets up front and a CF hood, just from those 3, you are looking at about 15-20hp gain.
 

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For every 100lbs lost you go about a 10th quicker in the 1/4. I think that's what you meant because if my engine was on an engine dyno it would make kick a$$ power!!!
 

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Its not really economical if you think about it in that sense alone. It'd probably end up being cheaper just making more power.

But less weight also improves the handling and braking of the car, making it feel lighter on its toes and more nimble as well.
 

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I will look at HOT ROD tomorrow and see what they tested on. Isn't your focus slower with someone else in the car?(not knocking you BANDIT) Did they talk about the 100lbs/.010 quicker theory or weight loss in general. The theory does very(I {think} a higher horsepower car would gain more than our focus). Might be the other way around????
 

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Discussion Starter #7
i didnt mean youre gonna dyno more power....heloo???

Its just hypothetically talking, your car will be faster by 10hp if you kept the weight verses loosing 100lb...get it?
Also, it is cheap up to a certain degree. Im getting seats just for the hell of it and cause they feel/look good. THe rear seat goes cause ive never once used it, that right there is about 150lb. Im getting a CF hood, again cause of looks, plus you loose about 20lb
 

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I knew that you meant that. I was just joking
. Sorry if it sounded differently.
 

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Also in the department of losing some weight...you could get rid of the heavy ass 26lb rims with some 14lb rims......replace the 21.5lb flywheel with a FS weighin in at about 8.5lbs........and get rid of the stock udp that weighs 3.4lbs and get an Unorthodox racing pulley that weights 7.8 ounces!!!!!! Just by doing these three things your gonna lose almost 65 lbs!!
 

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26lb rims? Your not talking about the stockers are you? They are a fair 'mount less than that.
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by BANDIT:
Hotrod magazine did a test on this & proved it wasn't true!
Sorry guys.
<HR></BLOCKQUOTE>

Excuse me? Hot Rod took a Cadillac from a 17 barge to a 12 second screamer by removing weight. When they were done, all that was left to the car was a seat, steering wheel and windshield.

My own testing on a Mustang and Focus has proved the 100# weight reduction = a 1/10th second reduction in ET. Nazthug is right on too when he says it would take an additional 10 hp to get the same improvement.

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ZX3Racing
Best ET: 14.76 @ 91.6
Naturally Aspirated
 

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The weight loss=HP gain is true to a point and I won't question anyones figures but "the law of diminishing returns" kicks in at some point. Loosing the first 100 lbs of weight may gain the equivalent 10HP, and maybe even dropping 200 lbs may gain you twenty but if you half the weight of the car (say 1300 lbs) you aren't going to gain the equivalent of 130 HP. This is because other things start to kick in like drag co-efficient, rolling resistance etc. Same idea if you put two 130HP Zetec engines in your car, it wont go twice as fast.
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by 2001 ZTS:
The weight loss=HP gain is true to a point and I won't question anyones figures but "the law of diminishing returns" kicks in at some point. Loosing the first 100 lbs of weight may gain the equivalent 10HP, and maybe even dropping 200 lbs may gain you twenty but if you half the weight of the car (say 1300 lbs) you aren't going to gain the equivalent of 130 HP. This is because other things start to kick in like drag co-efficient, rolling resistance etc. Same idea if you put two 130HP Zetec engines in your car, it wont go twice as fast.<HR></BLOCKQUOTE>

Do you base this on your own personal testing or is this just your opinion. As I have stated, I have data to back up this general rule of thumb. If you take any general rule to extremes, it will no longer be valid. I don't think anyone on this board will be testing this rule at its extremes so what is your point?
 

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Soooo, if I quit eating at Burger King and hit the salad bar instead I should get about 5 hp by Christmas


(all in fun
)

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"01 Yellow ZX3
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by ZX3Racing:
Do you base this on your own personal testing or is this just your opinion. As I have stated, I have data to back up this general rule of thumb. If you take any general rule to extremes, it will no longer be valid. I don't think anyone on this board will be testing this rule at its extremes so what is your point?<HR></BLOCKQUOTE>

I can't really be called just my opinion if it is based on the laws of physics. No one is argueing with your data, in fact I'm agreeing with what you said. Weight loss is an effective way to improve your power to weight ratio and thusly get better times. I put my motorcycle went on a weight reduction program years ago.

My only point is that it is not a linear relationship. My example of "halving" the weight of the car and not getting twice as much performance was just to keep the math simple. I dont expect anyone to shave more than half a tonne off a Focus or find a place for a second engine.

So what is my point? None I guess but if you think I'm wasting valuable space on the board you haven't been to the Off Topic section much.

-What did you have for lunch?
-Do you think Uma Therman is hot?
-What should I name my dog?
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I could go on and on.
 

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Let's see. I took a Zetec out of a contour, strapped it to a 1000Lb chassis.
Seems to be much quicker than any stock bodies I encounter.
 

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Your right, on paper halving the weight of the car does not double its acceleration.
In the real world things like wind resistsnce and traction get in the way.
With good traction your 1/2 weight car may acclerate nearly twice as fast to say 100mph but it will still have the exact same top speed as before, be it drag or redline limited. Also the faster you are going the less accelerative benefit you will see from reduced weight.

But thats not really the point of putting your car on a diet.

The BEST advantage of weight reduction isnt acceleration, its HANDLING. Less weight means less weight transfer! You will corner harder, brake faster, transition faster etc etc etc...

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Black 00' ZX3 5spd
Mods Dyno
"No Fear?..... Not Fast Enough!"
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by mark a:
Let's see. I took a Zetec out of a contour, strapped it to a 1000Lb chassis.
Seems to be much quicker than any stock bodies I encounter.
<HR></BLOCKQUOTE>

Yep, get yourself a Caterham 7 with a 140 hp Zetec and you've got one quick car!

Power to weight ratio, that's very important.
 

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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by ZX3Racing:
Excuse me? Hot Rod took a Cadillac from a 17 barge to a 12 second screamer by removing weight. When they were done, all that was left to the car was a seat, steering wheel and windshield.

<HR></BLOCKQUOTE>

Yep I remember this issue as well. It was classic seeing them cut up that car and running it down the track.

Like everyone else has said usually the equation is for every 100 lbs you lose it equals about a tenth of a second in teh 1/4, but hey who cares about drag racing its so simple to do!




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Team Focaljet:Great Lakes-Illinois Leader
2000 Battle of the Imports Bracket Champion Route 66 Raceway Joliet IL
2000 Autumn Orange ZX3
Esslinger Pulley,H&R springs,superchip,JBA header,Iceman intake,Vibrant exhaust
 
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