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Discussion Starter #1
I have been thinking about adding a rear swaybar as I want just a little more rotation in Autocrosses. I was resisting because It seemed to me that it was removing traction on the rear and he explains it perfectly.

Both videos taught me several things I had no idea mattered, in my case one thing was something to the effect that a balanced car will perform better on a track than a car with more traction.

This is on rear swaybars - excellent explaination and something I never thought about, how a rear swaybar stresses a clutch pumpkin

THis one is on cutting springs but talks about setting up diagonal weights by cutting front springs. Something I never thought of.
 

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For me, I have not been able to get my car to rotate on autocrosses, it likes to push, so its time to try one. If you are not experiencing a problem that a Rear Swaybar will fix, don't bother.

I watched most of his films, learned something in almost every one. I did the link wrong but check out the cutting springs one...
 

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I recently ordered the panhard bar kit from Mike. He's great to deal with and talk to, with a wealth of knowledge to pull from. Since the rear sway bar mounts to the panhard bar kit, I can add it in the future if I find I need it but I doubt I will but nice to have the option.

I used to have a rear sway bar on my 68 Chevy C-10 and ended up removing it a long time ago because I found it took away too much rear grip. The general rule in handling is stiffening up an end of the car removes grip, softening up an end will gain grip; which is how you gain balance - by stiffening or softening either end. If you have oversteer, for example, you can soften the rear or stiffen the front. For a rear drive vehicle, taking grip away from the drive tires doesn't always make sense, especially in a street car. Especially in a mustang with lots of power because you want as much rear grip as you can get to account for tire spin. You'll find rear drive cars get lots of front sway bar and front drive cars get lots of rear sway bar. If you're understeering in a rear drive car, you can add some throttle to spin the tires a little. Like Mike says in the sway bar video, it's a tuning aid if you end up needing it.

The other thing a person can do to gain balance in their car is by raising or lowering the roll centers. Lowering the rear panhard bar lowers the rear roll center and will also help remove grip from the rear, raising it will help gain grip. The rear roll center should be higher than the front roll center and it's the relation to each other that changes the balance. That's one of the things that goes wrong if the arning drop in the front is taken too far, close to 2" drop, it'll raise the front roll center to much and can lead to oversteer. You want the line connecting the two to be sloped downward toward the front. The easily adjustable MMI rear panhard bar should make adjusting the rear roll center height a breeze.
 

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For me, I have not been able to get my car to rotate on autocrosses, it likes to push, so its time to try one. If you are not experiencing a problem that a Rear Swaybar will fix, don't bother.

I watched most of his films, learned something in almost every one. I did the link wrong but check out the cutting springs one...
will it rotate on a road course? Try wider front tires and hard rear tires?
 

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Discussion Starter #7
No, not on a road course, its pretty close to neutral, the rear never comes around but it really doesn't push either - but no rotation, however in Autocross, it tends to push. I'm trailbraking to plant the front end turndown at the same time but I cannot get it to oversteer and throttle will make it plow. I would like just a taste of oversteer to get it to rotate. Hence I'm thinking back sway, I have an adjustable one so I should be able to dial it...
 

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what kind of diff do you have ? clutch type? For me the big take away from that vid was a rear bar could cause the diff to have issues .
Also would it fit with your WATTS ?
My car rotates pretty good I think, especially when I accidentally hit the clutch. SO probably no rear bar for me
 

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dobro, what is your weight distribution?

On the courses you run, what is the top speed you hit?
 

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See above...
I have all Global West front and rear and it will rotate under throttle. The del-alum bushings in the rear add roll stiffness and positively locate the rear axle. Maybe similar to a sway bar with rubber spring bushings? I also lowered the upper are more than the 1” arning drop.
 

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Discussion Starter #13
what kind of diff do you have ? clutch type? For me the big take away from that vid was a rear bar could cause the diff to have issues .
Also would it fit with your WATTS ?
My car rotates pretty good I think, especially when I accidentally hit the clutch. SO probably no rear bar for me
I don't really know what diff I have, its ford 9" narrowed 2" from stock and I had clutch plates replaced in another lifetime in California, My rear swaybar comes in from the rear so yes it can be installed without interfering with the Watts - thank goodness.

dobro, what is your weight distribution?

On the courses you run, what is the top speed you hit?
Never had my car on a scale, top speed in most autocrosses would be likely 55-60 in a quick sprint but I be the greater majority of autocrosses only hit 45 or so. I get deep in second gear occasionally but I wouldn't say its often. SCCA has rules about course settup to limit speeds.

Other than the battery in the trunk and heavier 351 up front but with all the aluminum on the motor I doubt its heaver than a stock 289.

I have all Global West front and rear and it will rotate under throttle. The del-alum bushings in the rear add roll stiffness and positively locate the rear axle. Maybe similar to a sway bar with rubber spring bushings? I also lowered the upper are more than the 1” arning drop.
My setup is all rubber eliminated from front end. Shortened stock UCA by 1/2 inch, Arning drop, 1.5* neg camber, 4.5 Castor, Red Konis, set at 3/4 up front 1/4 out back. 1" front swaybar. Rear Watts Link. Big Block springs .685" up front - 5 leafs with an extra half leaf clamped to the front half of the springs which are basically clamped solid with two clamps. Its not really that stiff out back surprisingly. This is a setup John at OT suggested me trying and I really like it. Completely eliminated spring wrap which was game changing in hard trailbraking on a course!
 
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