Loosing weight

[Mynute 1]

How much weight would one need to loose per wheel to make a difference in the horsepower or miles per gallon game? Hell, if I could stay away from all the bad foods I love I could probably make a big impact on both

[MINI-Fit]

Originally Posted by Mynute 1

How much weight would one need to loose per wheel to make a difference in the horsepower or miles per gallon game? Hell, if I could stay away from all the bad foods I love I could probably make a big impact on both

Based on tests run in a recent issue of Grassrootsmotorsports.

Loosing weight in the wheels, brakes, or tires won't help much for daily street driving. Just keep it reasonable.

You don't directly gain any HP and you don't necessarily gain any mpg.

If you loose weight it will help power to weight ration but total power stays the same.

If you have lighter wheels and tires you do have more nimble handling and response but that's not the same as power.

If you get more narrow tires like 185/60-15 or even 175/65-15 you'd reduce rolling resistance and weight but you'd loose some handling on corners. Everything is a bit of a trade off. Higher tire pressures also help a little for decrease rolling resistance and slightly better mpg but only a little.

Low tire pressure or a dirty air filter really hurts mpg. Driving fast and braking hard reduces mpg to some extent. Coasting and using cruise control can improve mpg.

For improved handling really sticky tires help the most. The stock tires are comfortable enough but are not good for handling. Sticky tires wear faster, good example is Bridgestone Potenza RE-01R in 195/50-15.

If you have performance track tires and you are driving at high speeds then lighter rims will help but only a little. A big difference will come from driving with skill (attend a driving school).

If you go into the opposite direction and get very heavy big wheels it will feel a bit sluggish when accelerating and slow to brake but for daily driving it's OK. Bigger wheels usually mean short sidewalls that are stiffer and that will help handling and turn in response but usually that can decrease comfort and increase road noise.

A general rule of thumb is don't go overly wide on the rim or tire.
If rim weight is about 14 to 17 lbs you're fine.

If you want to be weight conscious then don't add extra audio video upgrades or a huge subwoofer.

[Snap Fit]

Originally Posted by Mynute 1

How much weight would one need to loose per wheel to make a difference in the horsepower or miles per gallon game? Hell, if I could stay away from all the bad foods I love I could probably make a big impact on both

You can (probably will, I have) notice a difference if your wheel is lets say 16lbs and you go to a 9lb wheel. It will feel a bit more responsive and a bit more nimble. I have even heard of accelerations changing by as much as a 1sec reduction in 0-60 and it makes sense.
As far as mpg's I have only heard of increases of 2mpg or less.
The more drastic the change the more obvious it is. But your driving style indeed has much more to do with things.

nothing better than a lightweight 10" wheel, for all those classic mini fans

[mahout]

Sorry but wheel/tire combo weight has nothing to do with power. Lighter combos will assist acceleration but not significantly enough to warrant any purchase except for racing
Lighter combos are easier for the power you have to increase rotation of the wheel/tire combo and to decrease sprung weight for better suspension control but you pay a high price for not that much gain. As I said, for racing. A/X too and maybe especially.

[Mynute 1]

Thanks guys. I was considering buying a set of Desmond Regamaster Evos to help with the MPG. If it was able tp free up a pony or two I thought that woud be great. But, dropping $1500 to $1600 on a set of wheels without the bennys I was after is a lot for me to choke down. I am currious if the 9.5lb weight vs our stock 17lb would make a noticable difference in either area?

[kenchan]

given that the gross weight of the wheel and tire are considerably lighter
than stock you will notice better braking capacity and steering/handling
response.

acceleration....probably not much. bascially the rule of thumb is
for every 100lbs loss on the car, you gain 0.1sec improvement
during your 0-60mph acceleration.

so you'll definitely see some gains on data back to back, but getting
influenced by temperature/humidity will probably overwelm the 0.1 or
0.2sec benefit you gained especially on a daily driver.


your very best bet is to go forced induction.

[eldaino]

Originally Posted by kenchan

given that the gross weight of the wheel and tire are considerably lighter
than stock you will notice better braking capacity and steering/handling
response.

acceleration....probably not much. bascially the rule of thumb is
for every 100lbs loss on the car, you gain 0.1sec improvement
during your 0-60mph acceleration.

so you'll definitely see some gains on data back to back, but getting
influenced by temperature/humidity will probably overwelm the 0.1 or
0.2sec benefit you gained especially on a daily driver.


your very best bet is to go forced induction.

excellent info. I like solid proof over 'my car feels so much faster!' types of bullcrap. There are probably a lot of guys who buy uber expensive light weight wheels and stick em on their cars that are just daily drivers and never see drag races or track duty that would be upset to hear/read this type of stuff.


strangely though, they don't frequent this type of thread.

[Snap Fit]

Originally Posted by eldaino

excellent info. I like solid proof over 'my car feels so much faster!' types of bullcrap. There are probably a lot of guys who buy uber expensive light weight wheels and stick em on their cars that are just daily drivers and never see drag races or track duty that would be upset to hear/read this type of stuff.
strangely though, they don't frequent this type of thread.

Most of what we do to our cars though is about what it "feels like"
Most performance products never see the light of a closed course, heck most cars are never even used to their potential on the "streets" anyway.
Not even close.
There are alot of Ferraris that never see a track, yet oddly thats not what comes to mind when I see one. heehee (its mostly- "I hope this person hits my car"....I kid, I kid )