wheel weight - does it really matter?

[321 GO]

been looking at rims lately... and wondering how much difference does weight really make on acceleration?

choices so far:
motegi mr7 17" = 24.5 lbs
tenzo r av7 17" = 19.6 lbs
excel tz7 17" = ?

does 4.9 lbs(each)/19.6(total) really make a difference?

i had some g racing kugi 17s(26.25 lbs each) on my 00 hatch but with only 106hp anyway i wasn't really worried about it.

basically im definately getting 17"/white/7 spoke rims...just a matter of which ones. also, does anyone know of any other rims that fit this profile?

[BSEVEER]

I feel your pain bro, those are exactly the same kind of wheels I like, but I want silver to match the car. I really want a 7 spoke wheel (the Tenzo is the best color match for me) like the 3 you mentioned but they are a bit heavy. I want a wheel that isn't so heavy that it will hurt acceleration but I don't want to spend $1500 on wheels and tires. Why does this have to be so complicated:( j/k, I think cp-8's are a good alternative and the weight and price are ok too.:D...I think I'm starting to ramble...maybe I've had too much wine I dunno...

[Civicvtec1ps]

bought my rs limited concep pro. 17s for 110 piece.
18lbs .and looks great!

[adamslad]

Can you post some pics? I'm looking for a good set of 17s, along with tires. Since I live in NJ, I need tires that work in the shiz-nity weather we ALWAYS seem to have here!

[Civicvtec1ps]

Originally posted by adamslad
Can you post some pics? I'm looking for a good set of 17s, along with tires. Since I live in NJ, I need tires that work in the shiz-nity weather we ALWAYS seem to have here!

falken ze 512s are all season tires m+S

[BarracksSi]

Originally posted by 321 GO
....does 4.9 lbs(each)/19.6(total) really make a difference?

It's not about the total weight loss in terms of the whole car. That's, what, less than a one percent change?

5 lbs off a 25 lb wheel is a 20% difference in UNsprung weight ("unsprung" is the stuff that rests on the groung, and not suspended in the air by the suspension.. in other words, wheels & brakes are unsprung weight.. "sprung weight" is what's held off the ground by the suspension, that is, the rest of the car). Less wheel weight means that the suspension can move more quickly, letting the wheel respond to surface irregularities with better resolution.

It also partially means that the wheel itself can be accelerated more quickly. Less rotating mass = faster wheel acceleration.

At the same time, though, putting a higher percentage of weight at the perimeter will actually increase the wheel's inertia, making it more difficult to accelerate.

Bicycles that race on closed, velodrome tracks often have a disc rear wheel for two reasons -- aerodynamics and quicker acceleration.

Dragsters, we know, have small rims and h-u-g-e tires. The large tires allow for more rubber to be on the ground, true, but why not have big rims and low-profile super-wide tires? Lower rotational inertia, that's why.

High inertia will allow a wheel to roll longer once it's underway, requiring less engine power to keep moving. For high acceleration, however, low inertia will let a motor accelerate the wheel more quickly, which will -- of course -- accelerate the vehicle more quickly.

OK, now I'm rambling...

Does a 20% decrease in wheel weight make a difference? Yup.