i'm thinking of getting 15' rims for my box, but only if there are power and improved fuel efficiency. otherwise the cost may not be justified, at least for me. i don't mind looking stock
does anyone have stock 15' lightweight rims and have noticed a difference? thank you!

 

Well, 15 foot wheels would be gigantic, first of all. And they'd be heavy and bad on gas.

All kidding aside, if the wheels you get are lighter than what you currently have, you could see a marginal savings in fuel economy. It's hard to estimate real numbers, but lighter wheels would mean less weight for the engine to move so efficiency should improve. A little.

And I doubt you'd notice any change in power. Well, your power output would be the same, but again, it would have less weight to move, so it has the potential to be more responsive.

This all depends on the total weight savings and is all really minimal anyways.

 

oh thanks! also wondered if anyone had numbers. more responsive sounds good too, but i guess that would be hard to measure.

i meant 15" doh!!! (now i can use this emoticon!)

 

Ya, it would be nearly impossible to tell any real gains in "power" and responsiveness. You might feel something and think it's great, but it could all be in your head too. The gas mileage, however, would be something you could measure after getting them installed.

 

The stock steelies are 17-19 lbs (I can't remember exactly, but it's in that range); IIRC Koenig Heliums (Helia?) are only about 11 lbs, so you can definitely shave a fair amount of weight off. Tires don't all weigh the same, so that's something to look into as well. Obviously, narrower will tend to be lighter.

 

took the words right out of mouth

 

You need to remember that a weight savings in the wheels is compounded by the fact that they are also spinning. In addition to moving around along with everything else in/on the car, the wheels also use power to start them spinning, and the reverse with braking - you would stop quicker. The number I recall for this factor is four. Lets say you save five pounds per wheel, times four wheels, times four, thats like shaving eighty pounds from your ride.

 

Other than in actual competition scenarios, small differences in tire and wheel weight are pretty inconsequential, smaller than can be reliably measured...

Lightweight wheels are generally more easily damaged by curbs and road hazards, as well, unless you're talking about forged wheels, which are very expensive...

I have alloy wheels on my box, btw, but that's because I like the way they look...

 

Mine came with the 15" (6" wide) factory alloys with the stock 185/60-15s. This is a pretty darned lightweight combo. I now run 15 x 7 Borbet alloys with 205/55-15s. Although they handle light years better, they are heavier, and there's a MAJOR difference in both responsiveness and MPG. Granted, most of that is due to the sticky, wider tire's additional drag (and the fact that G-Force Sports are a fairly heavy tire), but the difference is obvious the moment you pull away from the curb.
I made a best of 43.6 MPG with the stockers; the best I've done with the aftermarket set-up is around 38 or so.