BlueS2000Boy

ok here is t he deal.... i was just wondering this myself...

everyone knows the more weight you add to a car the slower it is going to be. assuming you don't add horse power to compensate. but lets say i add 100 pounds to my S2000. now my question is. would it make a difference as to where he weight would be added in conjuction to how much slower the car would go. for instance. lets say i put 100lbs in the passanger seat, or 100lbs in the trunk. that is 100lbs added to one specific part of the car. or i add 100lbs to the whole car but spread the weight evenly say 25lbs each corner.... under what weight condition would the car be slower? if at all there would be any difference between the 3?... thanks

JustJustin

Slowest would be to put the weight on the wheels/tires...rotational inertia. While adding weight technically shouldn't change the top speed (unless you run really soft springs, and the weight reduces the ground clearance, or changes the aerodynamics)...Adding weight at the worst places would reduce acceleration.

-Justin

PS - Now the physics majors out thier can chime in with the formulas.

DaveOnLI

Initially, no, it doesnt matter.
Once you get up to a speed where aerodynamics plays a factor then if it was all in one place and the weight changed the drag coefficient you might reduce your top end.

rsaeini

adding weight to specific parts of the car will not make it slower but it will change the handling characteristics of the car.
for example, if you put the weight in the trunk it may cause the back end to slide out a bit under hard cornering when compared to putting that weight in the passenger seat. get it?

whenever i carry stuff with me i like to distribute the weight evenly so it doesn't change the way it handles.

Elistan

Are you talking straight-line acceleration? If so, I think that putting the weight in the back would give you a tiny bit of advantage. More weight over the rear wheels = more traction...

JustJustin

I too am honestly interested in the real-life dynamics of this one, as friends in go-karting are always interested in weight for handling and performance improvements.

Let's keep the assumptions simple:
1) Add 100lbs weight to a stock S2000
2) Assume weight does not directly impact aerodynamics (via really soft springs-or that the weight is not a "wing" or such device)
3) Assume the measurements we are interested are not handling nor braking, only acceleration and top speed.
4) Assume dry weather conditions where traction (or lack of) is not an issue.

Q) Based on the above, where is the best place to put the weight (if any) to improve performance (if it can be done)

SO where are all those true "car-nuts" who can actually tell us about the effects of static and dynamic?/rotational weight and their impact on acceleration and top speed?

-Justin

Tedow

You just assumed your way back to the first sentence in the original post: Everyone knows the more weight you add to a car, the slower it is going to be. Adding 100 pounds to the car will always make it slower. Force = mass * acceleration. You increase mass while keeping force (HP, torque) constant means less acceleration. Period. I suppose adding the weight to the back of the car would be marginally less penalizing than at the front from an acceleration perspective, since more weight on the back tires gives more traction during acceleration. However, they'd both be slower than the original car.

As for the original post, yes it makes a difference where the weight is place from a handling perspective. More weight in the trunk makes you more prone to oversteer. More weight in the passenger seat keep the car more level during right turns, less level in left turns. Weight far from the center of gravity of the car will make it more difficult to turn, due to the larger polar moment of inertia. etc etc...

nodisguise

More weight is always bad, no matter where you put it, unless you have a car with like 90% of the weight in front of the front wheels, in which case adding some weight to the rear might not be too bad.

Mr Payne

More weight in the trunk means it will oversteer?

Welshman

What is the point of this? Are you simply going to add weight for the sake of it so you just want to know whether to put the sack of cement in the boot or on the seat next to you or better still strapped to the bonnet so you can't see where you are going????????