Someone Prove It

[karl_1052]

Go outside and run down the street. Rest up until you are ready to do it again then try it with 20 lb lead boots on. See where I am going with this?

Read the actual test results I posted, not anecdotal stories.

[AKADriver]

Go outside and run down the street. Rest up until you are ready to do it again then try it with 20 lb lead boots on. See where I am going with this?

Thing is, light vs. heavy wheels is more like running in cross-trainers instead of specialized running shoes, not the lead boot extreme. There's some added weight and inefficiency, but it's at the margins, not a major difference.

I switched from 19 to 12 pound wheels on my car and there was a difference in the way the car felt but I doubt there was a real change in performance.

[AKADriver]

so i have lightweight pulleys on my car, its a 2004 gti vr6. ive had them on for probably close to 100,000 miles now. never had a problem. but, there is one thing, the crank pulley i took off, was just that, a pulley. there is no external harmonic balancer to be found on my motor. i think the problem are people removing the balancer for a pulley. there is a reason those balancers are on there. do u think car companies would be putting them on for decades if there wasn't a reason?

Right, on plenty of cars the pulley is just a pulley.

Interestingly, even though Subarus have a pulley that does have a damper built into it, Grimmspeed has this quote from Subaru of America on their website:

Thank you for your patience as I checked with our Technical Services Department regarding your message below. They advised that the crank pulley is a pulley and nothing else. It is not used as a harmonic damper/balancer. Thanks for the opportunity to be of assistance. If you need any future assistance, please feel free to contact us again."

Best wishes, John J. Mergen

Customer Service Department Subaru of America, Inc.

I still wouldn't buy one, as it's $130 that I don't think would actually do anything noticeable on a stock car in a double-blind test.

Oddly enough, Subaru published an SAE whitepaper about the EJ22T engine in 1989 which specifically calls out the pulley as a double mass harmonic balancer intended to disperse the torsional vibration of the crankshaft up to 7500rpm.

[The A1 and A2 German]

Hope for TCL?

An ~informational thread with proper content not turning into a high school drama.....almost feels like TCL 1.0

Carry on .

[Chris_V]

Go outside and run down the street. Rest up until you are ready to do it again then try it with 20 lb lead boots on. See where I am going with this?

Hmm. I went from the stock 17" wheels on my Mustang to 20s. No noticeable difference in any performance factor other than having better grip from stickier tires.

There. My anecdotal experiment cancels yours.

[todras]

Spun bearings in the SVT Contour Duratec engine are believed to be because of the crank pulley. A lot of guys install the one from the ST200 in europe. It's a heavier dual mass dampner. I know one I owned had one installed and never had any engine issues. Sold it with 160k on it. It's ok to do power steering and alternator pulleys but I'd never change the main crank pulley.

Here's a pic comparing the 2. Stock is on right obviously. Ford must have redesigned this for a reason.

[MJZman]

No, they don't make a big enough difference.

http://www.carcraft.com/projectbuild...ls_comparison/

In this article they dropped 82lbs of unsprung weight and the car only gained 1/10th

If anything, that article proves that it is a noticeable difference, IMO. Going from 12.14 to 12.03 is a pretty good gain from simply swapping wheels. Why in the world to you think that F1 teams, MotoGP, and LM cars use very lightweight magnesium wheels? It surely isn't for bragging rights.

[PowerDubs]

Not to mention that at low 12's, a tenth is a lot.

Now if we were talking going from 16.2 to 16.1, that would be different. The wind resistance alone at those cars traps would be hugely different.