OK so I'm buying some HX wheels to replace my 14" steelies and I need some help here understanding how the whole sprung/unsprung weight thing works. I've been reading the weight reduction 101 thread here - https://www.hondacivicforum.com/m_53543/tm.htm

And what I gather from this is that reducing the weight of the drive wheels (front two wheels in my case) has a 70% more positive effect, but reducing the weight of the "dead" rear wheels has no more positive effect than ordinary removal of weight from the chassis. Is that right? So all in all, if I replace my stock steelies (18 lbs per wheel according to this - http://www.superhonda.com/tech/wheel_weights.html - is that right?) and replace them with stock HX's (11.75 lbs per wheel) then I'm reducing the weight of the vehicle by 25 real lbs, but the effect will be the same as reducing the chassis weight by 54 lbs (6.25 x 2 = 12.5, divide that by .30 to account for the rotational thinger = ~42 lbs, then add... err, subtract 12.5 more lbs for the rear wheels for a grand total of 54 lbs)

Sooo... experts jump in. Am I thinking about this the right way?

 

If I understand it and you correctly then that sounds right to me.

 

I'm pretty sure it applies to all the wheels, not just the drive wheels. It's basically anything the car has to spin. Rotars, axles, flywheel, clutch, etc.

 

The engine doesnt directly spin the rear wheels, if it did it would be AWD not FWD. So hes right, removing weight from the rear wheels is the equivalent of removing weight from the chassis.

 

The engine still has to get them spinning. The only way it'd be different is if the front wheels were spinning out. I mean, I could be wrong but it just doesn't make sence that the rear wheels wouldn't be included. They'd still have the same intertial properties as the front ones.

Take this... a motor (the engine) has a gear on the shaft (front wheels) and another one running off that gear (rear wheels,) the motor (engine) still has to spin them both.

Says x4 not x2.

 

its more about rotational mass, not sprung or unsprung weight. that has more to do with handling than acceleration. but it does take more power to get the wheel weight spinning than it does to just drag it along (as in the rest of the mass of the car.)

 

Yeah... It's all about inertia.