How bad are heavy wheels?
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On The Tree
Joined: Mar 2010
Posts: 99
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How bad are heavy wheels? My 19's are quite a bit heavier than stock 16's, not sure how much though.
I know there isn't an exact answer to this, just wondering if anyone has experience running with heavier wheels, compared to stock or lighter wheels?
I know there isn't an exact answer to this, just wondering if anyone has experience running with heavier wheels, compared to stock or lighter wheels?
The heavier the rim simply makes the car slower and that is not even touching the subject of tire compounds or sidewall. From my exp Dyno's can pick up on the loss of HP and at the track weight that rotates amplifies compared to static.
Only way to know the diff is to weigh them.
In a perfect world where you got perfect traction from each tire/rim setup, just the spinning weight alone would make you slower. How much will depend on the individual car set up.
For you, if your running a M6, don't expect to set any records.
Only way to know the diff is to weigh them.
In a perfect world where you got perfect traction from each tire/rim setup, just the spinning weight alone would make you slower. How much will depend on the individual car set up.
For you, if your running a M6, don't expect to set any records.
I ran with 18's on DR's for years until I gave up and recently got some Weld's with ET drags. I did alot of suspension mods over the years too but I dropped .2 off my 60' without even trying on my 2nd pass with them. It was like a completely different car. Any weight you can remove is going to do nothing but help. Your lack of sidewall on the 19's is killing your traction. If you can get down in the 1.8's with those, consider yourself doing well. Your 16's will be a huge improvement over the 19's, but a true racing wheel with runners will help even more.
Gotta get drag wheels man. I shaved off roughly 70 lbs. going from 18"s to 15"s.
Gotta get drag wheels man. I shaved off roughly 70 lbs. going from 18"s to 15"s.
I've been told that every 25 lbs of rotational mass is worth one tenth in the 1/4.
I also know why.... It goes back to a basic engineering equation: I= rMr^2
I- mass moment of inertia, the energy required to rotate any object
r- (greek letter rho) a constant based on the shape of the object
M- mass of the object
r- Radius..... note that it is the radius squared
What does all that mean? The heavier your rotating mass, and (more importantly) the farther that mass is from the point of rotation, the more energy is required to both accelerate it and decelerate it....
Thus smaller/lighter tires and wheels, can be accelerated much easier, requiring less energy to do it. Even if the tread diameter remains the same, a smaller/lighter wheel helps significantly, you're bringing the mass down and reducing the radius.
this applies to all cars, not just for drag racing.
I also know why.... It goes back to a basic engineering equation: I= rMr^2
I- mass moment of inertia, the energy required to rotate any object
r- (greek letter rho) a constant based on the shape of the object
M- mass of the object
r- Radius..... note that it is the radius squared
What does all that mean? The heavier your rotating mass, and (more importantly) the farther that mass is from the point of rotation, the more energy is required to both accelerate it and decelerate it....
Thus smaller/lighter tires and wheels, can be accelerated much easier, requiring less energy to do it. Even if the tread diameter remains the same, a smaller/lighter wheel helps significantly, you're bringing the mass down and reducing the radius.
this applies to all cars, not just for drag racing.
The issue seems is that may work for the majority of cars running lets say 14's and into the bottom 12's but once you start going much faster the rule will not always apply the same.
It is of my opinion that every car is different, especially when you go from manufacture to manufacture, chassis to chassis etc etc. You wont really know until you run the car and thats still assuming you can get the same amount of traction given the difference in tire which 99.9999% of the time your not so there goes another varible.
The way I look at it is that you should go as light as you possibly can without endangering your safety and as long as you can enjoy it, that is all that matters. That goes for valve train, rotating assembly, rims/tires, drivetrain....
It is of my opinion that every car is different, especially when you go from manufacture to manufacture, chassis to chassis etc etc. You wont really know until you run the car and thats still assuming you can get the same amount of traction given the difference in tire which 99.9999% of the time your not so there goes another varible.
The way I look at it is that you should go as light as you possibly can without endangering your safety and as long as you can enjoy it, that is all that matters. That goes for valve train, rotating assembly, rims/tires, drivetrain....
