xejshinex

I have 06 TL and I believe OEM stock 17inch rim weight 25 lbs per unit
and I recently purchased ICW RACING WHEEL 107 MB which is 21 lbs per unit
there is 4 lbs difference, total of 16 lbs difference for a set of 4 wheels
do I gain wheel horsepower for having lighter wheels? if so then how much whp do I gain?

ifirahse

iTrader: (6)

Sorry I had to.

No, you don't gain any whp...

flydog

I disagree.

ifirahse

iTrader: (6)

Let me clarify...there might be a slight difference in handling, etc., but the amount of hp going to the wheels does not change.

ricgrrarrow

you will feel like you do, but it won't be by much. it's kinda the reverse affect of putting on 20s. if you have 20s on your TL you know what i'm talking about.. when you put a heavier wheel, you feel laggish or slower. when you put a lighter wheel, its gonna free up a little more power, but honestly 16lbs? that's not enough to say hp gain.

and btw the total weight of the wheel setup also depends on the tire wrapped around it. the OE wheels are about 27 lbs.

stillhere153

iTrader: (1)

it is the equivalent of you running the 50 feet with 16lbs belt... you will get there quicker... but dude you'd still be the same dude...

ps. ifi...

op got

xejshinex

icic so no hp gain but get very very slightly faster

jimsta

iTrader: (1)

And like ricgrr said, also depends on the weight of the tire you are using, unless you put the old rubbers on.

[VTEC]TL

Reducing rotational mass will help slightly with acceleration. No gain in power though. You also have to take into account wheel sizing. Your new wheel might be lighter, but it is also 18" vs. the stock 17" diameter. This places more weight further away from the hub. The further the weight from the hub, the more force needed to get it moving. So the weight savings are negated somewhat.

BLACKURA_NY

iTrader: (6)

are you guys sure? because i believe WHP is lost when adding heavier than stock wheels...

so wouldnt it kind of make sense that whp is gained with lighter wheels??

REMEMBEr, WHP is the amount of power hitting the pavement, not the power at the crank.... whp is lost due to drivetrain equipment and wheels/tires....

i think this is something we should experiment in a controlled environment

ifirahse

iTrader: (6)

I always thought whp was the amount of power going to the wheels, not from the wheels to the pavement. It's the wheel's job deciding how difficult to make it for the whp to actually turn the wheel hitting the pavement.

^ Please tell me that made sense...

TylerT

iTrader: (1)

I think BLACKURA_NY is making the most sense in this thread.

ballinfizzle89

iTrader: (6)

The car is able to use the power it is making more efficiently with lighter wheels as it has less rotational weight.

ifirahse

iTrader: (6)

That's what I'm trying to say. +1

BLACKURA_NY

iTrader: (6)

Correct.. and when dynoing, you are measuring the amount of horsepower at the WHEELS... if the wheels are lighter, they move quicker, less stress and rotatinal mass... thus, making the dyno (which reads the power at the wheels) read higher.... i could be wrong, but i think what i said makes sense..

dynos measure the power by the rollers which are being driven by the wheels.. if the wheels are lighter, they're gonna appear to be more powerful when under the same load from the engine...... and the dyno should read higher....

if you were measuing bHp, which is rated at the crank, wheels wouldnt make a damn difference.. or if you using a dynapack, which measures at the hub, again, wheels wont matter... but using a dynojet which measures from the, WHEELS, i think the wheels will make a difference.. my

sharp218

Interesting, I think you may have a point Blackura.
More energy (HP) would be needed to rotate the extra mass on the heavier wheels (which is taken away from the energy (HP) being sent to the ground).

ifirahse

iTrader: (6)

So if blackura's correct, does anyone know how much whp is lost for every pound increase of a wheel's weight? It might not even be enough to make a difference.

BLACKURA_NY

iTrader: (6)

i think it may be a noticeable difference.. case in point,with aftermarket wheels.... when you've got 19 or 20" wheels on a car, the car feels... a little more "sluggish"... thats why when you see cars at the track, they are usually on steelies, or lightweight wheels...

you dont see cars tracking that have 20" custom chrome wheels weighing over 30+ lbs

ifirahse

iTrader: (6)

I guess you're right. If you think about it, it's just like getting an underdrive pulley to free up hp. The pulley is a smaller or lighter wheel, the belt would be the road surface.

xejshinex

i think BLACKURA_NY is right. b/c on lighter wheels, you lose less whp

don5504

This man is correct. Wheel hp is the actual hp that is hitting the pavement. So lighter wheels will increase hp.

It does not change what the engine puts out though which is crank hp. It just basically optimizes what you already have.

D

SporkLover

Concur.... modified. Rule of thumb is lighter is better... but VTEC hit an important point as well. It also depends on how the weight is distributed from the center of rotation.

On an Apples to Apples comparison, and 18LB 17in rim will likely soak up less power than a 20 lbs 17 inch rim.....

however a 18lbs 18 inch rim may soak up the same amount of power as a 20lb 17inch rim because weight is being moved farther from the center of rotation.

Think of it this way.... when a figure skater does their spins... they turn faster as they pull their arms and legs in towards their bodies.... and slow down as they move them out.

Inaccurate

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