|
Re: Effect of wheel weight
[Re: Wedgeman]
#1443260
06/01/13 09:30 AM
06/01/13 09:30 AM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
I have heard that for 1 lb off the Wheel is like 80lbs off the body....
67 Barracuda
best 6.75 1/8 mile
No way.... a heavy wheel does take more power to
accelerate it BUT you also have to take into account
how far from center line of the axle the weight is...
if its a big 20" vs a 12" wheel
|
|
|
Re: Effect of wheel weight
[Re: MR_P_BODY]
#1443262
06/01/13 10:53 AM
06/01/13 10:53 AM
|
Joined: May 2012
Posts: 1,834
South Bend
John Brown
top fuel
|
top fuel
Joined: May 2012
Posts: 1,834
South Bend
|
I read an opinion by Porsche Engineering years ago that decreasing the weight of a rim by 1 pound was equivalent to removing 1.4 pounds of static weight.
July 19th should be "Drive Like Rockford Day". R.I.P. Jimmie.
|
|
|
Re: Effect of wheel weight
[Re: CHAPPER]
#1443263
06/01/13 10:55 AM
06/01/13 10:55 AM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
Quote:
I have heard that for 1 lb off the Wheel is like 80lbs off the body....
67 Barracuda
best 6.75 1/8 mile
8 lbs is a closer estimate. 
This is much more realistic ... but whats a 0 amongst
friends...LOL
|
|
|
Re: Effect of wheel weight
[Re: MR_P_BODY]
#1443264
06/01/13 01:31 PM
06/01/13 01:31 PM
|
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
StealthWedge67
master
|
master
Joined: Jul 2006
Posts: 4,319
Puyallup, WA
|
8 lbs even sounds like an over-estimate to me. think about it: that means if you save 5 lbs per rim, that's equal to 160 lbs off the car??? no way. I think the post above that references 1.4 as the factor is probably closer to accurate.
?????
Last edited by StealthWedge67; 06/01/13 01:32 PM.
LemonWedge - Street heavy / Strip ready - 11.07 @ 120
|
|
|
Re: Effect of wheel weight
[Re: StealthWedge67]
#1443265
06/01/13 03:09 PM
06/01/13 03:09 PM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
8 lbs even sounds like an over-estimate to me. think about it: that means if you save 5 lbs per rim, that's equal to 160 lbs off the car??? no way. I think the post above that references 1.4 as the factor is probably closer to accurate.
?????
That I understand but I was just saying that the
8# is more in line than 80#... the 1.4 might be real close..
I'm not positive on it
|
|
|
Re: Effect of wheel weight
[Re: MR_P_BODY]
#1443266
06/01/13 03:43 PM
06/01/13 03:43 PM
|
Joined: Nov 2003
Posts: 1,969
Chandler, AZ
Duner
top fuel
|
top fuel
Joined: Nov 2003
Posts: 1,969
Chandler, AZ
|
The factory Dakota wheels are HEAVY.
I dropped 25# per front wheel/tire and 14# per rear wheel/tire.
That's 78# at axle speed.
I'm really hoping it should be good for 2 tenths.
The link from BigBlockDart indicates that each pound at axle speed is worth roughly 3 lbs vs carried weight.
If I had a racetrack that was open I could find out!
Last edited by Duner; 06/01/13 03:48 PM.
|
|
|
Re: Effect of wheel weight
[Re: Wedgeman]
#1443268
06/01/13 06:06 PM
06/01/13 06:06 PM
|
Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
|
Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
|
Quote:
Ok....
I was questioning the effect of a very heavy wheel on the loss of ET because of the rotating mass
For example start with a 20lbs rim, make a few passes on a 3200 lbs car with 570hp...
Then given the same car with a lighter rotating mass at the rear with 11 lbs rims.........any change in ET ?????
You should see some gain but its not gonna be much
and it might not even show if the weather isnt the same...
but lighter is always better
|
|
|
Re: Effect of wheel weight
[Re: jcc]
#1443273
06/01/13 08:53 PM
06/01/13 08:53 PM
|
Joined: Jan 2003
Posts: 27,468
So Cal
autoxcuda
Too Many Posts
|
Too Many Posts
Joined: Jan 2003
Posts: 27,468
So Cal
|
Stick each wheel option on a Spintron and measure it. Done  Due to moment of inertia, two wheels with the same weight can take different amount of torque to rotate and accelerate. You could computer model/draft each wheel and put it into other software and give you the calculated difference. It's plug and chug right out of the book. I'm afraid the difference is so small that variables in track testing may not give you a precise number of what is going on.
|
|
|
Re: Effect of wheel weight
[Re: autoxcuda]
#1443274
06/01/13 09:27 PM
06/01/13 09:27 PM
|
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing
master
|
master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
|
This topic can be debated untill the cows or sheep come home. What we were always taught that the difference in rotational weight that has to be put in motion or unsprung weight as opposed to carried weight or sprung weight is for every reduction of 1# of weight that has to put in rotation is equivilant to a reduction of 8# of carried weight.IE:A reduction of 20# of power driven rotating drivetrain is like removing 160# of carried weight.This is only a rule of thumb since fricton and other causes of parsitic drag play a part in the rotation of componants.IE: Brake pad or shoe drag. Some good examples of lightweight componants are spools,axles,brake rotors,alum.hubs,driveshafts,wheels,tires and always the lightened engine rotating assemblies as well as trans assemblies.
|
|
|
|
|
