I have a 96 Prelude and am considering getting some 11 pound Volks. Stock weight is 19 pounds. Will saving 8 pounds per wheel (32 total) really make that much difference as far as acceleration?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hu &raquo;</TD></TR><TR><TD CLASS="quote">I have a 96 Prelude and am considering getting some 11 pound Volks. Stock weight is 19 pounds. Will saving 8 pounds per wheel (32 total) really make that much difference as far as acceleration? </TD></TR></TABLE>

I don't have first hand experiance but from what i have seen and the math I have done you are looking at something like every pound you save on your wheels is like shaving two or three pounds out of your back seat. You will/should however notice a lot more in terms handling, feel, suspension, and steering response.

Put it this way, if you jack up your front end, put it in gear, and mash the gas.....do you think it will take a lot longer for those other wheels to get to redline or will both sets spin really fast really quickly?

Cheers and ask if you have more questions.

 

Thanks for the reply. Its just hard to spend $1600 for some rims not knowing exactly how much it will help.

 

Acceleration? It'll improve by about 0.02 seconds in the 1/4

I didn't notice any difference I went from 18 pound steel wheels to 11.8 pound HX wheels.

It's also important to make sure you don't get anything bigger than 16's.
14's, just wish they were a little wider

 

You'd think that shaving off rotational weight off of your drivetrain would dramatically help your car accelerating. I'm pretty sure that if it were a high performance car, you'd definately see some sort of difference.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rst95eclipse &raquo;</TD></TR><TR><TD CLASS="quote">You'd think that shaving off rotational weight off of your drivetrain would dramatically help your car accelerating. I'm pretty sure that if it were a high performance car, you'd definately see some sort of difference.</TD></TR></TABLE>

It makes a difference but nothing compared to accelerating the actual weight of the car. Shaving weight of your tires will help reduce the unsprung weight which will help handling and suspension response. Again, I have no first hand experiance with this

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by me &raquo;</TD></TR><TR><TD CLASS="quote">

I am neglecting drag cause I am lazy.

Let:


T: torque at the wheels
I: total moment of inertia of the rotating parts
u: angular acceleration of the rotating parts
M: total mass of the vehicle
r: external radius of the tires
a: linear acceleration

T = Iu + Mra (1)
u = a/r (2)

(2) into (1)

T = I(a/r) + Mra
a = T(I/r + Mr)

Let R1 be inner radius of ring
R2 be outer radius of ring
m be the mass of the wheel.
I of a ring = 0.5m(R1^2 + R2^2)
I of cylinder = 0.5mR^2

So without knowing the actually weight distribution of the wheel wieght it is hard to give an exact % difference. But either way it seems you will see more effect from driving with a half tank of gas rather than a full tank.

it says here http://www.audiworld.com/tech/wheel13.shtml that adding about 10lbs of mass to your wheels is the same as adding 20lbs in your back seat.

The big thing for acceleration is the angular moment of inertia of the wheel, not the wieght, that's why you get different ratios from different sources. So if you have a lot of wieght at the centre of the wheel it is the exact same as just the same amount in your trunk, however if you move the weight to the outer edge of the rim it starts to make a difference.

In handling the wheels act as big gyroscopes. So if you have again a big angular moment of inertial you don't get as light a steering feel.

Lastly if the wheels are heavy the suspension can't move up and down as quickly, this the effect of making your tires do more of the absorbtion of work. Not to sure what other effects it has. It talks about it here.
http://www.tirerack.com/wheels...d=108

(however these results are not so cut and dry cause they varry the model of tire which will have a lot effect.)

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