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Discussion Starter #1 (Edited)
See my sig for the overall setup and car.

Here's the history: I installed all the MM components you see in my sig, with the A-arms in the lower position on the K-member and with the stock 5.0swaybars. I ran 2.8-3.0 degrees neg camber on track. The result was a far-improved car, but the dominant behavior in steady-state cornering was understeer. The outside edges of the front tires were being punished even with the negative camber.

Next step: I moved the A-arms up to the higher position, raising the roll center and improving the camber curve. Result: Steady-state understeer was even worse.

Next step: I installed a 4-cylinder front swaybar, the smallest available for the platform. Result: Much better, but a lot of body roll and still a little more understeer than I'd like. Tires throughout this process ranged from Kumho MX to Bridgestone RE-01R's to Dunlop Direzzas to NT01 R-comps. All of them in 245/45-17 on 17x8 wheels.

Latest step: I installed an EVM rear swaybar, set as stiff as a stock Cobra bar in its current setting. This is stiffer than the stock 5.0 bar I had on the rear. Result: Much improved balance, in fact a tendency to oversteer in the sharpest, flattest corner of Heartland Park (entry to turn 14, leading back onto the straight). Tire shoulders show some wear but not punishment. Right front tire still shows signs of scrubbing, although I'm careful to manage slip so the tires squeal, not scream and howl.

That's the setup you see in the video, starting at 1:25. I held up my buddy Dan in his 93 viper for a lap early in the session specifically so I could capture this :rofl:

http://videos.streetfire.net/video/HPT-TRACK-Touring-days_644178.htm

So, after all that is said...here's what I'm thinking. That's still a #### ton of body roll. It may in fact be worse off than trading theoretical lateral grip due to load transfer and flattening the car to keep the tires planted better. So do I put my stock 5.0 front bar back on, stiffening the front, and putting the rear bar at full stiff, which is something like 15% stiffer than it is now?

Thanks for reading.
 

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What about stepping up the spring rates?
 

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Discussion Starter #3
Not interested in doing that.
 

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I think you've kind of answered your own question. You feel the front roll is more than you'd like, you have a stiffer bar sitting on the shelf and the rear is adjustable...easy enough to do some testing at your next track session :)

What is your front alignment, btw? I'm thinking the adjustment range of the EVM bar may not be enough in the back to keep you out of understeer with the 5.0 front bar...just based on the other information you gave.
 

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Panama!!!!


BTW, I like how he put in the disclaimer, "Track Prepared Mustang" instead of just "Mustang."

If you are getting more roll than you want and you like the springs the way they are, it looks like you will have to play with the sways to get what you want. Since you already have the 5.0 bar, it won't cost you anything except a little of your time to install. I would try that first and see where it gets you. If nothing else it might give you something for comparison to help you narrow down what you need/want.
 

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Subscribing. I feel the same way towards body roll/spring rate as MFE does.

Also, I know this isn't swaybar/problem related, but do you think the 245 wide tires are holding you back(for the weight the car is)? I realize that sticky tires would only amplify body roll, but was just curious on reasoning for 245's. Are 275's a problem on the Fox cars?
 

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Discussion Starter #7
I'd absolutely be faster with more tire, but 275's would mean 9-inch wheels. 9-inch wheels means SN95-length axles or new studs in my current axles because there isn't enough stud in my current axles to support 1/2 inch spacers, and I'm just not in the mood yet.
 

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I'd absolutely be faster with more tire, but 275's would mean 9-inch wheels. 9-inch wheels means SN95-length axles or new studs in my current axles because there isn't enough stud in my current axles to support 1/2 inch spacers, and I'm just not in the mood yet.
Completely understandable, thanks!
 

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That Viper makes your car look like a little toy. I don't know whether it's that Foxes are tiny or that Vipers are freakishly large. You can definitely tell how much the rearend moved in that video though.
 

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MM advises against this. :confused: I sold off a 32mm Steeda front bar because it was too stiff according them/people on here.
Not at all being a smart ass, but if MFE wanted MM's book recommendations, he could have PM'd Jack. :)

My theory, which Jack may shoot all to hell, is that the rear is relatively softly sprung, and until the addition of the EVM rear bar, had very little rear bar (stock bars = the suck). With the TA and relatively low RC, it has been overpowering the front, creating false positives in the under-steer department.

If it were my car, I would try the bigger front bar, crank some more into the rear and see what it did. Also, if there is any adjustment on rear RCH, raising it a bit might make a big difference if there is still push. In my experience, a little bit of PHB adjustment goes a looooooooooooooooooong way.

My overarching thing here (besides being a big spring, big bar type of guy :)) is that with a lot of body roll, the front camber is all gone and with it, grip. The MM K member is good, but not that good. Heck, if I plug 5 degrees of body roll into SuspensionAnalyzer for my new car, the camber sucks and that is with an SLA with 19" long control arms.

Just thinking out loud, not arguing.

DaveW
 

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You guys take all the bind out of the ass end then you don't want it to roll and understeer. :rolleyes:
 

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Discussion Starter #14
Because now, when it slides, it's predictable and easy to recover. The curve of traction to no traction is very flat, compared to the uneven spike it was before.
 

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Because now, when it slides, it's predictable and easy to recover. The curve of traction to no traction is very flat, compared to the uneven spike it was before.
Are you comparing the 4 link to the TA or small bar to big bar?

DaveW
 

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Are you comparing the 4 link to the TA or small bar to big bar?

DaveW
Not at all being a smartass, but i'm pretty sure he's comparing the 4 link to a TA. Otherwise he would've EMAILED Jack H. about the differences instead of making a thread about swaybars. :rolleyes:
 

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Discussion Starter #19
Are you comparing the 4 link to the TA or small bar to big bar?

DaveW
What I have now to the 4-link. Yeah, it still slides, but it's so much more progressive. Less lateral acceleration and speed of the rear end when it gets loose, if you know what I mean. Less histrionics required to save it, and an infinitely improved probability of success.

Stock 5.0 bar is back on the front and the rear will be adjusted tomorrow. I have an event on the 14th, should be the same configuration so I'll actually be able to loosely compare times.

FWIW, the only video I have of this configuration dates back to 2007, at the last point I was on the old suspension before doing all the MM stuff. As it sat with the soft bar on the front, as of the event in the video, my good lap times were 5 seconds better, at 1:40, compared to 1:45 with the old suspension. When I get up to MAM I might be able to make a similar comparison.
 

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Discussion Starter #20
What is your front alignment, btw? I'm thinking the adjustment range of the EVM bar may not be enough in the back to keep you out of understeer with the 5.0 front bar...just based on the other information you gave.[/QUOTE]

On the track I'm running 3.0 degrees neg camber, whatever minimal toe-out I get from putting it there compared to my 1.25 street setting, and IIRC about 7 degrees of positive caster. I have to look up my records from when I set it all up. I never change the caster. I run minimal toe-in on the street, around 0 to 1/32 toe-in. My toe gauge isn't any more precise than that. It doesn't toe out much with the camber change.
 
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