If you worry about weight, wanna go forged and get a lightweight wheel then D2FORGED CV3 would be a good choice. With 20x10" - 20lbs and 20x13" - 21lbs it's a safe bet you won't be worrying about weight.

 

On both the build sheet (option Q9V) and window sticker, it says the wheels are chrome forged. Also in the 2010 brochure these are the only wheel options shown that say they are forged..even the Z model wheels which I would think would be forged...which is why I am asking.

 

Hmm, I decided to see if I could find some facts on wheel weight:


http://www.audiworld.com/tech/wheel13.shtml

read this ^^^^ !!

So.......
Using a quarter mile calculator ...and using my vette at approximately 3300 lb w/705 hp at the crank.
Then add 25lb (extra weight that aftermarkets typically add) x 1.7 = 42.5 lbs and I get a quarter mile difference of the following:

10.27 versus 10.31

Now lets take perhaps a worse case scenario:
All your aftermarkets are 32lbs per wheel that is approximatley a 36lb weight gain over stock ( C6 typical wheel weights: 22lbs fronts 24lb rears) ...and the ratio is 2x (instead of what the article discovered to be a truer number 1.7x)....thats a 72lb weight gain equivalent:

Use the calculator:
http://robrobinette.com/et.htm


10.27 vs 10.344

Who cares....




THis is based on straight line speed ...unsure what it would cause on corners etc...but I tend to not be concerned about that.

 

Lets carry this further he mentioned calculation in the article of 6 to 8x ....so lets take a look at that...

8x 36 (all aftermarkets 32 lb) = 288 lb ....so lets plug that in as the worst worst case scenario:

10.27 vs 10.56...

Now most aftermarkets will not weight that much and I am sure the calculation of 8x is way too high as he mentions in article...but even in that scenario it is not that detrimental....and you would never feel that in the streets.

So lets average things because we are doubters and dont believe the low number nor the highest number......his 1.7 round up to 2x ....the top number 8x = average them ...gets you about 5x ...aftermarkets realistically will add probably most often 25 to 28 lbs....so lets use 28...now lets use the calculator...that a 140lb weight gain....

Use calculator:

10.27 vs 10.41



I am leaning towards believing the lower number because we as consumers are always given B.S. to try to sell us things...

So the range is a loss of probably:

1/2 to 1 1/2 tenths of a second....

Make a difference in the streets? NO
On the track...sure everything matters there...


I think I am going to stick with my good looking, cheap, china Z06 reproductions...unless someone can find some mathmatical proof that proves the above to be incorrect.

 

Where is your mathematical equation for differences in braking distance, suspension reaction time, skid pad differences, gas mileage, for moving speed acceleration and deceleration? Things that are seen in the real world, not just a very roughly-estimated equation that attempts to show the difference in quarter mile times.

How about your actual test data on the subject, where all variables are equal?

What you did is a great attempt, but won't reflect real-world results.

Ps: cutting off .3 seconds off of your ET is a pretty big deal, actually. Since you like rough equations:
Racers 1/4 Mile Rule of Thumb for 10 second to 15 second cars: 100lbs = 10rwhp = 1mph = .1 second = 1 car length in 1/4 mile.

So your .3 second slower ET is like losing 30rwhp or adding 300lbs. That's pretty bad.

 

Yep I wish I would have had the chance to bring mine to the strip before ditching the run flats for lighter all-season radials. Last weekend I ran a best of 12.109 with 3/4 tank of gas. And aside from switching the tires, she's bone stock right down to the OEM air filter. It may cancel out as I lightened it up, but traction most likely suffered. My point is, I now REALLY want an 11 second slip without any modifications or running a drag radial - and every little bit counts when you are trying to shave off a tenth and 9/1000th of a second . . .

 

I agree with what you said, and agree that lighter wheels make a difference. THis was not an analysis trying to refute that lighter wheels do nothing for performance.It was to quantify the question of - What degree of difference do heavy wheels make in straight line performance? We all know it will damage performance but to what degree? We also all know that at the track it all matters. Although the analysis is not perfect (its not my data it is data I found) at least it is mathmatical proof of the difference based on all other variables being held constant. I believe some drivers may think the drop in performance is higher then it really is and this analysis was done to help them.

Some variables you mentioned make a difference in other aspects of driving our cars but not in straight line performance. Ex. braking distance,gas mileage However the other 3 variables are in question: suspension reaction time, skid pad difference, for moving speed acceleration and deceleration...however I wonder to what degree these variables are effected by an extra 3lbs per wheel and what are its effects on straight line performance? If you can provide some proof to what degree of difference? I would like to see that.

Everyone knows lighter wheels make a differrence - it is the degree of difference that I am interested in. Then we as consumers can take that degree of difference and ask ourselves the question. Are the look of these wheels worth the 1/2 tenth of second loss in performance? Since we are all different ....maybe. maybe not.

Also note you pulled from my data the most unrealistic and improbable scenario:
At .3 seconds... I am unsure how you looked at all the data and selectively pulled this out to make your point. Please read the article I hyperlinked first.
The article states that the calculation x8 is incorrect. I only calculated it at x8 as an improbable calculation. I also used unrealistic aftermarket weights of 32 lb per wheel. The actual results based on wheel weight is (based on article) a difference of less then 1/2 of a tenth of a second...not .3 seconds.

Also I think you tried to educate me to the obvious with your P.S. above....when I state that ".3 is not that detrimental" It was relative to the unrealistic and improbable calculation. I was referring to the fact that even in the most unrealistic and improbable calculation - and if you had the heaviest POS wheels available at 32 lb each.(most aftermarkets wheels are NOT this heavy) ... the grand total loss of speed is .3 tenths of a second. I personally thought in such an exaggerated worst case calculation -that the time loss would be much worse.

Now I am going to go look for some lighter wheels....

 

Even by using your lesser value, a .14 second difference, that still equates to 14rwhp or 140lbs of dead weight. Which, to me, is still fairly significant.

 

Yea, I hate knowing that some wheels are taking any thing from my performance ...

However, 5000 for some forged wheels for 1 1/2 tenths of a second is for someone who has exhausted all other forms of mods (supercharger, headers, meth etc. ) that will produce a much more significant increase in speed for less. This is simply logical.....however owning a corvette and adding mod after mod and trying to go faster for no reason ( like I did) is not logical so dont listen to me....

 

Thanks for the tip, Ed! I decided to pull the trigger on the TSWs. Tire shop called this morning to let me know they arrived and app't scheduled for Saturday morning install

 

Sure would like to see pics after you get them installed!!!

 

Absolutely