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I really didnt know where to post so here it is. I have been thinking about this for awhile, so i know reducing weight of any car is a positive thing, but with our car being fwd is it a good or bad to reduce the weight by cb hood, light weight battery tray & lighter battery and anything else that takes away weight from the front wheels. I know that rwd cars need more weight on the rear so they get better traction but with our fwd car is it positive or a negative to have less weight on the front (engine)
 

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Less weight on my Protege's front = My rear wheels and tires slipping when changing lanes causing me to have an accident with it

but the 6 is a different car, Much heavier....Lightening the weight on it can only be beneficial
 

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Discussion Starter #4
Less weight on my Protege's front = My rear wheels and tires slipping when changing lanes causing me to have an accident with it

but the 6 is a different car, Much heavier....Lightening the weight on it can only be beneficial
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Yeah but isnt it true that if there is more weight pushing down the tires there will be better traction?

so less weight would mean less traction? right
 

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Having a heavy front end as in FWD will hurt a car's handling in curves causing it to under-steer

Magazine reviews have given the 6 wonderful praise about the 6 steering in handling and have compared that portion characteristic to the BMW 3 .... of course it's missing the RWD of the Bimmer and does not handle entirely alike .... but is an accomplishment in itself (steering-wise) to be compared to the Bimmer nonetheless

Now if you are to change weight proportions of your 6 , expect to affect stock-tuned steering characteristics somewhat .... most likely giving the steering a much lighter feel to what it already is .....

There are suspension parts that can remedy handling such as a Strut-Tower Brace -over & under engine- G-Load Brace, K-Member , Sub-Frame Connectors , etc.
 

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Less weight on my Protege's front = My rear wheels and tires slipping when changing lanes causing me to have an accident with it[/b]
Sounds like a driving mistake caused the accident. Did you have a big rear sway bar too? And did you lift on the throttle?

but the 6 is a different car, Much heavier....Lightening the weight on it can only be beneficial
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The driving dynamics are nearly exactly the same.

Yeah but isnt it true that if there is more weight pushing down the tires there will be better traction?

so less weight would mean less traction? right
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No! No way! I know I've posted this before (try searching for "coefficient of friction"), but here it is again.

The coefficient of friction of a tire (ANY tire) goes DOWN the more weight you put on it. Suppose a tire with 400lbs of weight on it can hold up to 500lbs of lateral force. That same tire with 800lbs of weight on it may only hold 800lbs of lateral force, and with 1200lbs of weight on it may only hold up to 1000lbs of lateral force. Beyond a certain weight the tire becomes saturated much more quickly. So, while a tire with more weight on it does have more grip, it is disproportionate to the amount of weight that it now has to move around.

Thus, more weight is NEVER good.


Having a heavy front end as in FWD will hurt a car's handling in curves causing it to under-steer [/b]
Front heavy isn't bad so long as you tune for it. For maximum acceleration, you want most of your weight on the front tires. The point here is that if you could drop 200lbs off the rear of your car, it would have a much higher percentage of the car's weight on the front tires. You might think this would cause understeer (and it would without other changes), but it'd just take a larger rear sway (or firmer rear springs) to make the car handle similarly. Yet, it'd be much faster due to the lower weight.

I think dropping weight in the rear may be (speaking from theory, not experience) more beneficial than the front, to an extent, because weight in the rear is furthest away from the car's center of gravity. This gives the car a high polar moment of inertia, making it slower to change direction. And, since the rear wheels don't do anything in a FWD car, any weight back there seems pretty unnecessary- it's just dead weight that the front wheels have to work harder to tow around.

Drop too much weight off the rear and your spring rates may get a little ridiculous for street use, and you'll tripod around every turn. That's obviously not beneficial either. But some have an attitude that adding weight in the trunk (racing with the spare tire in or with a full tank of gas) is beneficial and this is wrong.

The bottom line is that you should try to lose weight wherever you can because it is ALL beneficial.
 

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interestingly percieved Stretch :)

Now there is only so much weight you can take off the back in everyday use body-wise (track-wise more) but I agree that tuning is a major factor nonetheless as soon as you start moving parts/weight around .... so better have a planned package set-up , or be ready for awkward response from mismatched parts/placement ....
 

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....... The point here is that if you could drop 200lbs off the rear of your car, it would have a much higher percentage of the car's weight on the front tires. You might think this would cause understeer (and it would without other changes), but it'd just take a larger rear sway (or firmer rear springs) to make the car handle similarly.
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For optimal neutral balance, constant speed corner, the roll stiffness balance is related to the weight balance. Dropping 200 lbs (sprung weight) off the rear causes oversteer, not understeer. Using limit logic, if it's 800 lbs off the rear, you would be tripoding at 1/4g, unless you softened the rear.

Agree with non-linear coef of friction at contact patch, but for street tires, 400 lbs off front may decrease initial acc'n rate, as % reduction in tractive force is greater than % reduction in total weight. Would have to run numbers ....
 
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KevinK2
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