BEST ANTI ROLL BARS
03-06-2006, 03:56 PM
#1
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Thread Starter
Join Date: Apr 2003
Posts: 118
now that i am upgrading the bushings, and have new coilovers in my car, I am also probably going to upgrade the sway/antiroll bars. Which company's product is the best to buy? (HKS,Tanabe,suspension techniques, eibach) does anybody have any of these, and how much better is each over stock?
also recently, ive found that the stock 300zx rear swaybar is actually stronger/more rigid that some of the aftermarket replacements. im just curious as to see if this is the same w the rx7.
also recently, ive found that the stock 300zx rear swaybar is actually stronger/more rigid that some of the aftermarket replacements. im just curious as to see if this is the same w the rx7.
03-13-2006, 03:34 PM
#4
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Join Date: Nov 2002
Posts: 3,108
Best bar = no bar. Since you have coilovers. Tune the coilovers's spring rates and rebound dampening so that you get the correct roll stiffness for the front wheels and the rear wheels without the need for a roll bar. Don't worry about compression dampening yet. Rebound is what affects "handling" weight shift.
Once you have everything done. Then select the roll bar to tune for driver preference.
Remember a roll bar makes a independant suspension less independant. Defeating the point of independant suspensions. If you have too stiff a roll bar then what happens is when you corner hard the Outside tire will see lots and lots of force, causing the suspension to compress. As the outside suspension compresses the A-arm will move up and thus twist your antiroll bar. A bar in torsion is like any other spring. It will a reaction force and the only reacting force is the downward force imposed by the inside wheel's a-arm. As you can see when the outside a-arm moves up, it will cause the inside wheel to move up.
That's bad. To get max cornering speed you want to make each wheel utilize it's traction to the maximum. How can you maximize the inside tire's traction when you are trying to lift it? Force of friction is defined by the downward force x the coefficient of friction. THe harder you push down the more friction force there is. Hence wings on F1 cars.
Make sure you tune your suspension before you tune your roll bar. Roll bar is the last on the list to tune on your suspension system.
Once you have everything done. Then select the roll bar to tune for driver preference.
Remember a roll bar makes a independant suspension less independant. Defeating the point of independant suspensions. If you have too stiff a roll bar then what happens is when you corner hard the Outside tire will see lots and lots of force, causing the suspension to compress. As the outside suspension compresses the A-arm will move up and thus twist your antiroll bar. A bar in torsion is like any other spring. It will a reaction force and the only reacting force is the downward force imposed by the inside wheel's a-arm. As you can see when the outside a-arm moves up, it will cause the inside wheel to move up.
That's bad. To get max cornering speed you want to make each wheel utilize it's traction to the maximum. How can you maximize the inside tire's traction when you are trying to lift it? Force of friction is defined by the downward force x the coefficient of friction. THe harder you push down the more friction force there is. Hence wings on F1 cars.
Make sure you tune your suspension before you tune your roll bar. Roll bar is the last on the list to tune on your suspension system.
03-13-2006, 04:32 PM
#5
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Join Date: Jan 2003
Location: London, Ontario
Posts: 2,871
Originally Posted by Cheers!' post='807718' date='Mar 13 2006, 04:34 PM
Best bar = no bar. Since you have coilovers. Tune the coilovers's spring rates and rebound dampening so that you get the correct roll stiffness for the front wheels and the rear wheels without the need for a roll bar. Don't worry about compression dampening yet. Rebound is what affects "handling" weight shift.
Once you have everything done. Then select the roll bar to tune for driver preference.
Remember a roll bar makes a independant suspension less independant. Defeating the point of independant suspensions. If you have too stiff a roll bar then what happens is when you corner hard the Outside tire will see lots and lots of force, causing the suspension to compress. As the outside suspension compresses the A-arm will move up and thus twist your antiroll bar. A bar in torsion is like any other spring. It will a reaction force and the only reacting force is the downward force imposed by the inside wheel's a-arm. As you can see when the outside a-arm moves up, it will cause the inside wheel to move up.
That's bad. To get max cornering speed you want to make each wheel utilize it's traction to the maximum. How can you maximize the inside tire's traction when you are trying to lift it? Force of friction is defined by the downward force x the coefficient of friction. THe harder you push down the more friction force there is. Hence wings on F1 cars.
Make sure you tune your suspension before you tune your roll bar. Roll bar is the last on the list to tune on your suspension system.
You miiight want to do a little reading here; http://www.carrollsmith.com/.
You must not have made this statement in front of him at any of the SAE competitions, he likely would have beat you to death with an anti-roll bar.
03-15-2006, 09:53 AM
#7
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Join Date: Dec 2003
Location: Mid-West
Posts: 791
Originally Posted by TYSON' post='806210' date='Mar 6 2006, 06:41 PM
If you're after 'best' bar none, consensus would be the Tri-Point adjustable setup. Cost is $650 for the front $140 for a rear to go with it.
They don't advertise it on their site anymore.
No pictures, so I'm not sure, but I think this is the same bar.
http://silverstone.fortunecity.com/brabham...uspension3.html
03-16-2006, 11:23 AM
#8
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Join Date: Nov 2002
Posts: 3,108
Originally Posted by TYSON' post='807740' date='Mar 13 2006, 05:32 PM
You miiight want to do a little reading here; http://www.carrollsmith.com/.
You must not have made this statement in front of him at any of the SAE competitions, he likely would have beat you to death with an anti-roll bar.
03-16-2006, 11:59 AM
#9
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Join Date: Jan 2003
Location: London, Ontario
Posts: 2,871
Originally Posted by Cheers!' post='808245' date='Mar 16 2006, 12:23 PM
if you like I can quote the section in tune to win by carroll smith on his views of antiroll bars and further quote teh section on roll stiffness from race car vehicle dymanics from William Milliken.
You mean this?
umm, yeah, he says to choose springs only hard enough to keep the car from bottoming out or wallowing over bumps, and use roll bars to tune out roll.
Formula cars have roll bars. If the best setup was no roll bars, surely a formula car could do that? Never mind a potential street car.
03-17-2006, 01:27 PM
#10
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Join Date: Dec 2001
Location: Richmond, B.C.
Posts: 136
Our A-Mod guru met with the late Carroll Smith during one of CS's lectures. This topic was discussed and Carroll mentioned how many ppl mis-interpret what he wrote. His writing was based on racing vehicles, and as such, we he says "soft" settings it's is still super stiff in roadcar standards. The cars he discusses have susp travel in centimeters not inches. So relevance must be taken into account.
The Tripoint is very nice and adjust (w/ various endlink points and tube diam)...I was told this is basically a circle track bar and can be sourced cheaper than via Tripoint.
Here's the TP setup:
The Tripoint is very nice and adjust (w/ various endlink points and tube diam)...I was told this is basically a circle track bar and can be sourced cheaper than via Tripoint.
Here's the TP setup: