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Suspension Rear Sway Bar just installed

Suspension Springs, struts, coilovers, sway-bars, camber plates, and all other modifications to suspension components for Clubman (R55), Cooper and Cooper S (R56), and Cabrio (R57) MINIs.

Suspension Rear Sway Bar just installed

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Old 03-15-2019, 03:11 PM
Velothree
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Rear Sway Bar just installed

For those of you who haven't installed a aftermarket upgraded sway bar, do yourself a favor and install one. Transformed my car's handling in corners. OMG!! This is how the car should have come from the factory.

I installed a ALTA 22mm bar.
 

Last edited by Velothree; 03-15-2019 at 06:00 PM.
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Old 03-15-2019, 05:56 PM
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+1

i did the 25mm Hotchkiss.
You aren’t just whistling Dixie my friend.
 
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Old 03-18-2019, 11:29 AM
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Great to hear - planning on installing an NM rear sway in the next couple months once I find a free weekend.
 
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Old 03-18-2019, 12:24 PM
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Originally Posted by Velothree View Post
For those of you who haven't installed a aftermarket upgraded sway bar, do yourself a favor and install one. Transformed my car's handling in corners. OMG!! This is how the car should have come from the factory.

I installed a ALTA 22mm bar.

Now get a front one, it will transform the car even further.
 
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Old 03-18-2019, 12:35 PM
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+1 Front sway bar
 
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Old 03-18-2019, 01:01 PM
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So, after 13+ years of modding, autoxing, tracking, modding, tracking, Dragon slaying.........my R50 MINI, i can say that the larger rear sway bar is by far the best mod to dial out understeer and help our cars go thru turns faster. Not a fan of upgrading the front, the difference between rear and front is what helps dial in the oversteer that makes my MINI so fast.
 
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Old 03-18-2019, 02:05 PM
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Originally Posted by colinmini View Post
So, after 13+ years of modding, autoxing, tracking, modding, tracking, Dragon slaying.........my R50 MINI, i can say that the larger rear sway bar is by far the best mod to dial out understeer and help our cars go thru turns faster. Not a fan of upgrading the front, the difference between rear and front is what helps dial in the oversteer that makes my MINI so fast.
A rear bar doesn't dial out understeer, it accentuates over steer, the front still plows.
A larger matched front bar will reduce also understeer.
I pulled the trigger on my F56, and will never go back to saying a just a rear bar is good enough.
 
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Old 03-18-2019, 03:56 PM
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Originally Posted by TVPostSound View Post
A rear bar doesn't dial out understeer, it accentuates over steer, the front still plows.
A larger matched front bar will reduce also understeer.
I pulled the trigger on my F56, and will never go back to saying a just a rear bar is good enough.
Mmmm, not sure I’m finding that info. I will do more research, guessing less roll up front could help. I have always used:
For more oversteer: stiffen the rear(or soften the front, it’s all about balance)
For more understeer: soften the rear(or stiffen the front)

My 25mm rear hollow bar with it’s three adjustments allow for big swings at dialing in my MINI. I then tune the Koni Yellow shocks and then fine tune the RE-71R tire’s air pressures. Set-up notes are kept at every track(MidOhio, Nelson Ledges, etc.), autoX location and Dragon. I include ambient temps and track conditions too.

I love my rear sway bar, best first mod. Lol
 
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Old 03-18-2019, 05:48 PM
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Originally Posted by TVPostSound View Post
A rear bar doesn't dial out understeer, it accentuates over steer, the front still plows.
A larger matched front bar will reduce also understeer.
I pulled the trigger on my F56, and will never go back to saying a just a rear bar is good enough.
Very well said. It is about balance. Having the front plow, as he says, the car looses front camber. Look at my signature for my sway bar combination. I can attest to the fact that it doesn’t understeer, unless I have my foot on the gas.
 
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Old 03-18-2019, 05:49 PM
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Less roll up front helps the tires stay in contact with the road, and gives better turn in response. A large factor in the front pushing out (understeer) is the loss of camber during body roll. Limit the body roll, and the tires will work better.
 
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Old 03-18-2019, 06:07 PM
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Originally Posted by TVPostSound View Post
A rear bar doesn't dial out understeer, it accentuates over steer, the front still plows.
A larger matched front bar will reduce also understeer.
I pulled the trigger on my F56, and will never go back to saying a just a rear bar is good enough.
I dont know what kind of thinking this is but its false. Vehicle manufacturers design with safety 100 percent of the time. Cars are designed to loose control front bumper first. Front impact accidents are always the safest in any car. Front tires loose grip first by design, period! If vehicle manufacturers had cars going off the road sideways everywhere there would be huge amounts of deaths and lawsuits. By enlarging the rear sway bar we reengineer the handling of the car to allow it to go into a corner flat. If we loose control and hit a pole and kill a passenger as a result of the swaybar change the manufacturer is absolved from wrongdoing and we get sued. Think of Porsche and a certain movie star. Those things are death traps because they corner flat. When they loose grip they dont hit head on. Back to a mini, if you increase both rear and front sway bars equally you will still end up with a nose heavy car, just with less body roll.
 
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Old 03-18-2019, 06:32 PM
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I'm not done
weight transfer, by enlarging the rear bar you transfer front weight to the rear wheels. Thus the front is lighter and rear is heavier. The goal if to transfer as much weight equally as possible. You want all four tires to get equal weight and not overcome the elasticity of any single tire.
Regular old passenger car tires are the safest tire that can be put on a car. High performance tires are considered unsafe on unaltered cars. When a passenger tire and performance tire loose their modulus of elasticity they do so in two different fashions. A passenger car tire loses grip sooner but holds the road much longer. A performance tire holds harder but loses that hold very quick once the modulus of elasticity (MOE) is passed.
how does this relate to sway bars?
think of an unaltered car with aftermarket performance tires. The front end is designed to be heavy to go off the road first. Once the performance tire has lost its MOE the car is very hard to recover and in a nose first crash. Now same car with passenger tires. The car may be in a nose slide going off road but because it still retains some grip you may be able to steer it to safety.
by and large the best change to a vehicles cornering performance is with a larger sway bar.
one last comparative study, if anyone has pulled a heavy trailer they have probably used a load distribution hitch. Like a sway bar they distribute the weight away from the actual ball, moving the center of gravity towards the front of the tow vehicle. This is very similar to a sway bar, it moves the weight around the vehicle for best performance.
 
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Old 03-18-2019, 06:56 PM
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Yes by far the rear sway bar is the best bang for the buck. For the 2nd gen cars we always use our WMW 25mm hollow rear bar same as the Hsport. It on the middle setting is ideal and has bushings with a proper grease channel that will hold the grease and keep it quiet longterm. Also being a hollow bar it only weights 5.5lbs vs 12-14lbs of a solid 22mm bar, both are the same stiffness.
https://www.waymotorworks.com/wmw-rear-sway-bar.html
 
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Old 03-19-2019, 12:10 AM
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Originally Posted by I like mini clubman's View Post
I'm not done
weight transfer, by enlarging the rear bar you transfer front weight to the rear wheels. Thus the front is lighter and rear is heavier. The goal if to transfer as much weight equally as possible. You want all four tires to get equal weight and not overcome the elasticity of any single tire.
Regular old passenger car tires are the safest tire that can be put on a car. High performance tires are considered unsafe on unaltered cars. When a passenger tire and performance tire loose their modulus of elasticity they do so in two different fashions. A passenger car tire loses grip sooner but holds the road much longer. A performance tire holds harder but loses that hold very quick once the modulus of elasticity (MOE) is passed.
how does this relate to sway bars?
think of an unaltered car with aftermarket performance tires. The front end is designed to be heavy to go off the road first. Once the performance tire has lost its MOE the car is very hard to recover and in a nose first crash. Now same car with passenger tires. The car may be in a nose slide going off road but because it still retains some grip you may be able to steer it to safety.
by and large the best change to a vehicles cornering performance is with a larger sway bar.
one last comparative study, if anyone has pulled a heavy trailer they have probably used a load distribution hitch. Like a sway bar they distribute the weight away from the actual ball, moving the center of gravity towards the front of the tow vehicle. This is very similar to a sway bar, it moves the weight around the vehicle for best performance.
^ that is all unmitigated BS.

Most front engine cars have > 50% of their weight on the front wheels. Front wheel drive cars like the MINI are 60/40 or even 65/35, there's never going to be equal weight on all 4 tires. Sway bars don't change the weight distribution front/rear at all, they change stiffness side to side at the front or rear. And it isn't modulus of elasticity - it's coefficient of friction. Pictures of front wheel drive cars autocrossing or on track often show the inside rear wheel in the air in hard cornering, so the coefficient of friction for that tire is zero, but the car is still going around the corner even with the "front end heavy".

You're making a dangerous, stupid, and factually incorrect generalization when you say "high performance tires are considered unsafe on unaltered cars." What about a stock BMW, Porsche, or Corvette? The handling of my Mini (and my lap times) improved dramatically when I got rid of the "regular old passenger car tires" (the stock runflats) and put on Michelin Pilot Super Sports. Better tires means better roadholding which means better cornering, better handling, better ability to maneuver to avoid an accident, less likelyhood of understeer OR oversteer. Period. But Michelin PSS tires, as good as they are in dry or wet conditions, would be impossible on snow or ice, just as all season or snow tires are the wrong thing for the track or autocrossing. The safest tire for a car is the one that provides the best traction for the conditions at the moment. Now if you put high performance tires on the front and a set of crappy worn out tires on the back, you'd have a problem but that would be moronic.

Most modern cars have the suspension tuned for understeer, that's because 99% of drivers can't deal with oversteer. They go into a corner too fast, the car starts to understeer, the instinctive reaction is to lift off the gas and perhaps brake, which (generally) brings the car back into line and the driver stays in control. (The exception is pre-1990s 911s where initial understeer followed by a lift is a good way to experience oversteer.) Not because a head-on crash into a tree is safer than a tail-first crash into a tree, it's because it's the best way to keep 99% of drivers in control if they get a little bit past the limits.

One of the inherent limitations in cars with MacPherson strut front suspensions (such as the MINI) is camber loss during hard cornering due to body roll - the top of the tire is leaning toward the outside of the turn, which reduces the contact patch and therefore the coefficient of friction. Two ways to help solve that, one is stiffer springs, the other is increased negative camber. MINIs really benefit from increasing the negative camber in front, anyone who autocrosses or tracks their car will tell you that. When I added camber plates and had the car aligned for -2 degrees of camber all around, it totally transformed the car.

I highly recommend this video titled "The Physics of Racing"
, it explains all of this stuff. Very educational.
 

Last edited by squawSkiBum; 03-19-2019 at 09:54 AM.
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Old 03-19-2019, 07:08 AM
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Originally Posted by squawSkiBum View Post
^ that is all unmitigated BS.

Most front engine cars have > 50% of their weight on the front wheels. Front wheel drive cars like the MINI are 60/40 or even 65/35, there's never going to be equal weight on all 4 tires. Sway bars don't change the weight distribution front/rear at all, they change stiffness side to side at the front or rear. And it isn't modulus of elasticity - it's coefficient of friction. Pictures of front wheel drive cars autocrossing or on track often show the inside rear wheel in the air in hard cornering, so the coefficient of friction for that tire is zero, but the car is still going around the corner even with the "front end heavy".

You're making a dangerous, stupid, and factually incorrect generalization when you say "high performance tires are considered unsafe on unaltered cars." What about a stock BMW, Porsche, or Corvette? The handling of my Mini (and my lap times) improved dramatically when I got rid of the "regular old passenger car tires" (the stock runflats) and put on Michelin Pilot Super Sports. Better tires means better roadholding which means better cornering, better handling, better ability to maneuver to avoid an accident, less likelyhood of understeer OR oversteer. Period. But Michelin PSS tires, as good as they are in dry or wet conditions, would be impossible on snow or ice, just as all season or snow tires are the wrong thing for the track or autocrossing. The safest tire for a car is the one that provides the best traction for the conditions at the moment. Now if you put high performance tires on the front and a set of crappy worn out tires on the back, you'd have a problem but that would be moronic.

Most modern cars have the suspension tuned for understeer, that's because 99% of drivers can't deal with oversteer. They go into a corner too fast, the car starts to understeer, the instinctive reaction is to lift off the gas and perhaps brake, which (generally) brings the car back into line and the driver stays in control. (The exception is pre-1990s 911s where initial understeer followed by a lift is a good way to experience oversteer.) Not because a head-on crash into a tree is safer than a tail-first crash into a tree, it's because it's the best way to keep 99% of drivers in control if they get a little bit past the limits.

One of the inherent limitations in cars with MacPherson strut front suspensions is camber loss during hard cornering due to body roll - the top of the tire is leaning toward the outside of the turn, which reduces the contact patch and therefore the coefficient of friction. Two ways to help solve that, one is stiffer springs, the other is increased negative camber. MINIs really benefit from increasing the negative camber in front, anyone who autocrosses or tracks their car will tell you that. When I added camber plates and had the car aligned for -2 degrees of camber all around, it totally transformed the car.

I highly recommend this video titled "The Physics of Racing" https://www.youtube.com/watch?v=bYp2vvUgEqE, it explains all of this stuff. Very educational.
Do your home work, center of gravity is changed by sway bars. I've been building cars for 40 years, I've got a pretty good understanding of how they work.
 
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Old 03-19-2019, 07:57 AM
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Originally Posted by colinmini View Post

Mmmm, not sure I’m finding that info. I will do more research, guessing less roll up front could help. I have always used:
For more oversteer: stiffen the rear(or soften the front, it’s all about balance)
For more understeer: soften the rear(or stiffen the front)


Basically, this is true.
But, and there is always a but (because there are very few absolutes, especially with suspensions), there is more to it than just this.

Getting back to your comment about balance, what you said works well for “setting up” car. That is, once you have put in what you want in the way of sway bars, shocks and springs, you can change how the car handles by making changes in stiffness in the direction you said to have the impact on handling that you say. Last year I had the opportunity to help a friend “tune” the suspension on his MINI. He installed Ohlins coilovers and a 22mm RSB. We had access to a wetted skid pad and a paved autocross course with sharp turns and elevation changes. The way he described his initial setting was that the car was almost undriveable because it had too much oversteer. By stiffening the front shocks and softening the rear shocks he was able to transform the car to about neutral as he described it. He has since put the RSB on a softer setting, which has allowed him to soften the front shocks and stiffen the rear shocks to improve the compliance and transitional response of the car.

But, this also points to the complexity of setting up a suspension. Things are interconnected and a change to one thing will impact something else. For example, a swaybar is very effective at increasing the roll stiffness of the car. But on the other hand, a sway bar increases the connection between the left and right side of the suspension which decreases the independence between the two sides. This means that if you run over the corner curbing on a race track with one wheel, the other wheel is affected. So, to gain back some independence, a softer sway bar can be used in conjunction with stiffer springs to retain the roll stiffensse. But stiffer springs have their downside too. It is all about trade-offs to achieve the balance that you want, along with the compliance and vehicle dynamics.

Originally Posted by colinmini View Post
My 25mm rear hollow bar with it’s three adjustments allow for big swings at dialing in my MINI. I then tune the Koni Yellow shocks and then fine tune the RE-71R tire’s air pressures. Set-up notes are kept at every track(MidOhio, Nelson Ledges, etc.), autoX location and Dragon. I include ambient temps and track conditions too.

I love my rear sway bar, best first mod. Lol
And I see that you are doing just that...
Sorry for the extended explanation above...
But can you imagine all of the notes that the top IMSA teams have???!!!

As for adding a large front sway bar, if you just change the front bar, then the effect will be more understeer. But if you pair it with a larger rear sway bar, then you can look at the stiffness ratio between the front and rear to see what the approximate change in handling will be. For example, MINI and BMW spend millions to develop good and great handling cars (no one would say that the E36 M3 is not a good handling car). So I look at them as someone who understands the whole package; much better than I ever could. I would think that people would agree that the MINI Cooper S handles better than the base Cooper; the JCW handles better than the S and the JCW with the JCW sports suspension handles better then the base JCW. With each of changes MINI uses larger front and rear sway bars, along with stiffer springs and shocks. In looking at just the sway bar changes, in most cases they increase both sway bars by one mm (the JCW sport suspension is a 0.5 mm change). The effect is to both increase the overall roll stiffness of the car (car corners flatter) and to proportionally give the rear a greater increase in stiffness than the front, which will decrease understeer. For me, I liked the handling of the JCW base suspension and the balance the car had on the track. It was a nice compormise between good handling and “safety” when I come upon the undesirable “unknown” on the track. So, I targeted my front and rear sway bars to have about that same front to rear stiffness ratio, with the rear swaybar on it softest setting. On its stiffest setting it will be less than the JCW sports suspension (e.g.: less understeer than that suspension). The bonus I got was that the increased overall roll stiffness of the car reduced the undesirable camber change on both ends of the car. For experience, this has been the progression of the the following MINIs I have had out on the track: a base S, a base S with a 20 mm solid RSB, a S with the optional sports suspension (which is the base JCW suspension) and my current setup (RSB on the softest setting). My experience has been that each one, in that order, handles better than the one before. Now, for autocross (which I also do, but not overly seriously), I would have a different setup, with even more rear bias to the car’s roll stiffness, if I was serious.

 
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Old 03-19-2019, 08:10 AM
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Originally Posted by I like mini clubman's View Post
Do your home work, center of gravity is changed by sway bars. I've been building cars for 40 years, I've got a pretty good understanding of how they work.
As with a lot of things, it is not as simple as that.

Center of gravity is the location of the car’s center of mass with respect to the sides of the car, the front and rear of the car and how high that mass is off the ground. In a static situation sway bars make no change to the center of gravity (other than their own mass, which is minimal with respect to the car).

In a dynamic situation sway bars will change the dynamic center of gravity. But, that will be at the expense of traction at the end the weight is being transferred too. Hence, part of the reason a MINI will readily swap ends with just the addition of a really large RSB.
 

Last edited by Eddie07S; 03-19-2019 at 08:12 AM. Reason: Typo
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Old 03-19-2019, 09:40 AM
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I posted somewhere about the F/R Eibachs feeling like the factory setup (favoring understeer to neutral) just more aggressive/responsive feel. I would not go back to the factory bars.
Note: I've seen people do the same job (engineers/tradesmen/mechanics etc) for many years and do it wrong.
 
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Old 03-19-2019, 12:07 PM
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Sometimes it's done so wrong you will see a car going around a bend on three wheels. The center of gravity is so far removed that the wheel in the air weighs exactly nothing. If a triangulation of the center of gravity is done you would see that it is way outside of the car itself.
I also teach about "center of gravity" for a living. It's in an industrial environment but I have studied this crap for a while. I lowered my first car in the mid eighties and, heaven forbid, I put four tires and rims that were all the same on it. Most people were still putting big honking tires on the back and jacking it up to the stratosphere.
still the cheapest way to improve road performance is to add a rear sway bar and lower it. Center of gravity moves back towards the middle of the car and is lowered closer to the road surface.
 
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Old 03-19-2019, 01:18 PM
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Originally Posted by I like mini clubman's View Post
Sometimes it's done so wrong you will see a car going around a bend on three wheels. The center of gravity is so far removed that the wheel in the air weighs exactly nothing. If a triangulation of the center of gravity is done you would see that it is way outside of the car itself.
I also teach about "center of gravity" for a living. It's in an industrial environment but I have studied this crap for a while. I lowered my first car in the mid eighties and, heaven forbid, I put four tires and rims that were all the same on it. Most people were still putting big honking tires on the back and jacking it up to the stratosphere.
still the cheapest way to improve road performance is to add a rear sway bar and lower it. Center of gravity moves back towards the middle of the car and is lowered closer to the road surface.
True, the least expensive change is a rear sway bar. Lowering takes a bit more effort/money (coilovers or replacement springs) and may get into compromising how it is on the street (main reason I haven’t lowered mine). If I understand your comment, I think you are also saying that you can have “too much of a good thing” (Sometimes it's done so wrong you will see a car going around a bend on three wheels. The center of gravity is so far removed that the wheel in the air weighs exactly nothing.). Maybe we jumped over this point when we said to add a front sway bar, but that was what we were thinking when we made that suggestion. That is, when the RSB gets large enough it would be a good idea to match it with a larger front sway bar. Hopefully, I correctly understand your comment.
 
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Old 03-19-2019, 01:41 PM
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This chart is a useful rule of thumb tool...
when comparing front to rear amends

https://www.whiteline.com.au/docs/bu...e%20BL-281.pdf

for example I went and added 26mm front to existing 20mm rear superpro recently 80% to 144% front to rear
But I still need to add back Summer tyres to this mix with a repeat track day before I can confirm if this was a worthy upgrade
so currently I have nothing else to add to this debate in terms of user feedback,...
 

Last edited by blue al; 03-19-2019 at 02:41 PM. Reason: nb roadster will be different to most others here
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Old 03-19-2019, 11:20 PM
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Originally Posted by I like mini clubman's View Post
Sometimes it's done so wrong you will see a car going around a bend on three wheels. The center of gravity is so far removed that the wheel in the air weighs exactly nothing. If a triangulation of the center of gravity is done you would see that it is way outside of the car itself.
I also teach about "center of gravity" for a living. It's in an industrial environment but I have studied this crap for a while. I lowered my first car in the mid eighties and, heaven forbid, I put four tires and rims that were all the same on it. Most people were still putting big honking tires on the back and jacking it up to the stratosphere.
still the cheapest way to improve road performance is to add a rear sway bar and lower it. Center of gravity moves back towards the middle of the car and is lowered closer to the road surface.
"a triangulation of the center of gravity" can't ever show that it is outside of the car itself. The center of gravity, or more accurately the center of mass of an object, is always inside the body of the object. For it to be outside of the object, here would have to be some mass that magically appeared outside the object but was somehow connected, or some part of the object would have to have negative mass, which doesn't exist (unless you count anti-matter.) The center of mass is always going to stay in the same place inside the car. (Technically it will move slightly due to movement of the wheels and suspension components, but that effect will be very small because of the magnitude of the masses moving - wheels, tires, etc. - are small compared to the mass of the rest of the car.) The reason a car might be on 3 wheels during hard braking is because the springs are soft enough that the car can pitch and roll far enough to one corner that it exceeds the downward suspension travel on the opposite corner. The wheel and tire still have the same mass and are creating a downward force (weight) on the car, but are not supporting the car or providing any lateral acceleration.

When people talk about "weight transfer" under braking or cornering, etc. what is really going on is the change in the moment around the car's axis of roll or pitch causes an increase in force on one axle or side and a decrease on the other. It is easier for people to think of it as "weight transfer", but the center of mass of the car is still in the same place, just the forces that support the car have moved due to the moments changing, which changes the forces on the tires and therefore the relative grip of each tire. Lowering the car is beneficial because it reduces the moments since the center of mass is lower relative to the roll and pitch axes of the car. Stiffening the rear sway bar won't move the center of mass, the only way to move the center of mass toward the rear of the car is to either remove weight from the front, or put a sandbag in the trunk.

Check out the Physics of Racing video, the guy is a physics professor who autocrosses and does time attack, he took the time to derive the equations and do the research and then explains it in a way that anyone can understand.
 
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Old 03-20-2019, 08:06 AM
squawSkiBum
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I was thinking about my assertion that the center of mass is always inside the body of the object, and realized that there are some cases where this is not true, for example a toroid (donut), or a U shape like a horseshoe. In those cases the center of mass is outside the body, but still within the 3 dimensional envelope of the object, which is the point I was making about the car.

I agree that a stiffer rear sway bar is the best bang for buck modification for handling. Next is better tires, then lowering. Lowering is a tradeoff though, stiffer springs and reduced suspension travel mean a harsher ride.
 
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Old 03-21-2019, 08:48 AM
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Originally Posted by squawSkiBum View Post
Stiffening the rear sway bar won't move the center of mass, the only way to move the center of mass toward the rear of the car is to either remove weight from the front, or put a sandbag in the trunk.
If you have a rear sway bar installed of a size that causes the inside rear tire to come off the ground, would that not have the same net affect as “moving” the CG? It would seem that would be the same as putting the car on scales, one under each tire and then compressing the suspension at one rear corner (eg: with a spring compressor; something not touching the ground) until its scale reads Zero. The scale diagonally across from should read lighter and the two remaining scales should read heavier. Maybe the term “CG” is the wrong term for this, but if the weight on each tire is changing with the dynamics of the then there must be some way to describe what is happening in the terms of the static weight of the car.

Sorry, I am more thinking out loud here and have not viewed the video you posted a link to. Maybe that will fill things in for me about this question.
 
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Old 03-21-2019, 09:37 AM
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Center of gravity is the correct term for this discussion. COG can move outside of a vehicle. This is how a car would roll over taking a corner to quick for its abilities. This is the same with heavy equipment to which I train people for a living. Its is a difficult concept to accept that somethings weight can be outside of its physical properties but it is how it works. There are more things going on with a vehicles suspension than can be discussed here. For anti sway bars it's the same. They help prevent body roll and transfer weight side to side and front to back by balancing the center of gravity.
agian manufactures create nose heavy cars for safety purposes. To balance this out we add a stiffer rear bar to move the COG more central to the car. It may be called an antisway bar but it is moving weight around.
 

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