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Old 07-01-2022, 02:06 PM   #15
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Do you not have adjustment in the rear?
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Old 07-01-2022, 02:12 PM   #16
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I increase neg camber about 0,5 a side(about -3.7) at the track. Can`t say I notice a toe change and car turns in stronger/crisper/nicer/harder( not sure of the word to best describe). Tires definitely approve wear wise.
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Old 07-01-2022, 02:43 PM   #17
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Do you not have adjustment in the rear?
Nope, all stock arms. Honestly not too worried about the rear, the front more camber-critical.
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Old 07-01-2022, 03:03 PM   #18
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I increase neg camber about 0,5 a side(about -3.7) at the track. Can`t say I notice a toe change and car turns in stronger/crisper/nicer/harder( not sure of the word to best describe). Tires definitely approve wear wise.

Front toe doesn’t change much with camber with Mac strut. Going more negative probably toe’d it in a touch which would be less noticeable if it went out. The rear changes a lot when you adjust camber.
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Old 07-07-2022, 09:29 AM   #19
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My findings-- front grip isn't all about front camber. I spent most of last season trying to find more front grip- new SPL control arms, crash bolts, etc etc etc, I was getting about -4.5 camber up front and was maxed out before I rubbed on stuff inside the wheel well.


I tried crash bolts first, and my sway bar endlinks started hitting the frame rails after installing the crash bolts, so I removed the crash bolts and bought a set of SPL FLCAs and tie rod ends. I got the FLCAs set up nicely- no bump steer, roll center in a happy place, etc etc. roughly -3.5 to -4 camber, which was more than I had before with crash bolts.

next race, the understeer/overall balance was marginally better but I did have more front grip. still angry about the understeer tho.

A fellow racer suggested I stiffen up the rear sway-- sometimes the trick to obtaining better balance is by reducing grip on the stuck end, not by increasing the grip on the sliding end..
Sooo, I stiffened up the rear sway a notch from where it was when I bought the car (assuming it was set up correctly to begin with...) HORRY SHEET WHAT A DIFFERENCE! suddenly the car rotates mid-corner as I roll into the throttle and I can steer the exit with the rear... overall grip has even improved-- on the long sweepers I used to have to feather the throttle around 25% to keep the front end from washing out, I can now take same corner about 90% throttle and accelerate through the sweep and STILL have some steering wheel to point the car. Niiiiice.

Same tires, same day, same conditions otherwise-- I dropped over 1.8sec on the next session and lowered the track record by 1.5sec.

I didn't take tire temps after, but the results on the clock are obvious and the tire wear on the outer shoulders was much better.

Sooo ummm, maybe you could consider looking at what you're doing in the rear and try to stiffen it up a little, vs more and more camber up front. Just my $0.02.
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Old 07-07-2022, 11:20 AM   #20
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sometimes the trick to obtaining better balance is by reducing grip on the stuck end, not by increasing the grip on the sliding end..
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overall grip has even improved
It certainly sounds like you did increase front grip.

A larger rear sway does not just reduce rear grip...you do get more evenly loaded front tires which is good and means more front grip. Not the magic solution for everyone or every car, but it can definitely work for some when done right.

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Old 07-07-2022, 12:34 PM   #21
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A larger rear sway does not just reduce rear grip...you do get more evenly loaded front tires which is good and means more front grip. Not the magic solution for everyone or every car, but it can definitely work for some when done right.

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Exactly!
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Old 07-07-2022, 01:08 PM   #22
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My findings-- front grip isn't all about front camber. I spent most of last season trying to find more front grip- new SPL control arms, crash bolts, etc etc etc, I was getting about -4.5 camber up front and was maxed out before I rubbed on stuff inside the wheel well.
Yeah, agreed. In my experience, with no downforce production cars with compromise street/track spring rates, there's a quite *broad* range of camber that will work well. I think I noted a slight improvement/reduction in understeer with the ~0.5 degrees more negative camber up front, from -3.0 to -3.5 between Palmer CCW last month and Palmer CW this past weekend.

Quote:
A fellow racer suggested I stiffen up the rear sway--
Sooo, I stiffened up the rear sway a notch from where it was when I bought the car (assuming it was set up correctly to begin with...) HORRY SHEET WHAT A DIFFERENCE! suddenly the car rotates mid-corner as I roll into the throttle and I can steer the exit with the rear... overall grip has even improved-- on the long sweepers I used to have to feather the throttle around 25% to keep the front end from washing out, I can now take same corner about 90% throttle and accelerate through the sweep and STILL have some steering wheel to point the car. Niiiiice.
Yeah, I have front/rear Eibach sways set to the softer setting up front and stiffer setting rear. I might consider throwing the stock front sway bar back on for more front grip, but that would cost some overall roll stiffness so more camber loss at the outside front strut... Handling was pretty good at Palmer the other day though, going to leave sways as they are for now. Might take the stock front sway with me to Palmer though.

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Same tires, same day, same conditions otherwise-- I dropped over 1.8sec on the next session and lowered the track record by 1.5sec.


Quote:
I didn't take tire temps after, but the results on the clock are obvious and the tire wear on the outer shoulders was much better.

Sooo ummm, maybe you could consider looking at what you're doing in the rear and try to stiffen it up a little, vs more and more camber up front. Just my $0.02.
Yeah, if I get frustrating understeer at Thompson might just try the front swaybar swap...
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Old 07-07-2022, 03:13 PM   #23
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A fellow racer suggested I stiffen up the rear sway-- sometimes the trick to obtaining better balance is by reducing grip on the stuck end, not by increasing the grip on the sliding end..
Sooo, I stiffened up the rear sway a notch from where it was when I bought the car (assuming it was set up correctly to begin with...) HORRY SHEET WHAT A DIFFERENCE! suddenly the car rotates mid-corner as I roll into the throttle and I can steer the exit with the rear... overall grip has even improved-- on the long sweepers I used to have to feather the throttle around 25% to keep the front end from washing out, I can now take same corner about 90% throttle and accelerate through the sweep and STILL have some steering wheel to point the car. Niiiiice.
A larger rear bar to help with rotation is something I learned with FWD platforms but people on this forum swears by stiffer/larger front sway bar to mitigate understeer. I am very confused now. LOL.
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Old 07-07-2022, 04:16 PM   #24
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A larger rear bar to help with rotation is something I learned with FWD platforms but people on this forum swears by stiffer/larger front sway bar to mitigate understeer. I am very confused now. LOL.
These cars don’t come with enough front roll stiffness from the factory. Stiffer front end helps mitigate camber loss due to body roll and thus tends to improve front grip a small amount while increasing responsiveness, net win.
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Old 07-07-2022, 05:38 PM   #25
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A larger rear bar to help with rotation is something I learned with FWD platforms but people on this forum swears by stiffer/larger front sway bar to mitigate understeer. I am very confused now. LOL.
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These cars don’t come with enough front roll stiffness from the factory. Stiffer front end helps mitigate camber loss due to body roll and thus tends to improve front grip a small amount while increasing responsiveness, net win.
*If* on a compromise stockish or street/track setup, I'd say roll stiffness in general is what's lacking, not *front* roll stiffness specifically. Adding a stiffer front bar helps reduce roll, but exacerbates overloading of the outside front. On some cars/setups it might be a net positive for front grip, but IMO better to increase roll stiffness at both ends or just the rear of the car to reduce understeer. I went with Eibach front (softer setting, ~150% stiffer than stock) and rear (stiffer setting but also ~150% stiffer than stock), which worked pretty well. May still swap the stock front bar back in at Thompson next Fri/Sat if frustrated with understeer...
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Old 07-07-2022, 06:45 PM   #26
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*If* on a compromise stockish or street/track setup, I'd say roll stiffness in general is what's lacking, not *front* roll stiffness specifically. Adding a stiffer front bar helps reduce roll, but exacerbates overloading of the outside front. On some cars/setups it might be a net positive for front grip, but IMO better to increase roll stiffness at both ends or just the rear of the car to reduce understeer. I went with Eibach front (softer setting, ~150% stiffer than stock) and rear (stiffer setting but also ~150% stiffer than stock), which worked pretty well. May still swap the stock front bar back in at Thompson next Fri/Sat if frustrated with understeer...
You have stock rear control arms, correct?
I have some Whiteline RLCAs on my car, and there are multiple holes for both shock and sway bar mounts. Thus I have additional spring and sway bar rate adjustments by moving the bar through those holes.
Just a thought you might be able to stiffen the rear up a lil more with something like that vs. reducing front bar.

As mentioned elsewhere, "more total bar" increases overall roll stiffness. since you're on a spring/shock combo, you are already compromising body roll compared to a coilover with track-oriented spring rates. thus you need even greater roll stiffness )on both ends) than a car with stiffer springs in order to keep the body lean in check.
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Old 07-07-2022, 06:56 PM   #27
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It certainly sounds like you did increase front grip.

A larger rear sway does not just reduce rear grip...you do get more evenly loaded front tires which is good and means more front grip. Not the magic solution for everyone or every car, but it can definitely work for some when done right.

- Andrew
I didn't think of it in that perspective, but yes you're right there. Now that I'm thinking about it, the stiffer rear bar indeed puts more weight on the inside front tire, which in turn reduces load on the outside front.

The data didn't really show any increase in peak cornering Gs, but the car definitely handled better and I was able to carry more speed in the long sweepers and rotate the car at/after the apex. initial turn-in was never a problem with either setting, but mid corner and exit suuucked once I got off the brakes and took weight off the nose. I use to have to ride the curbs afte the apex to make the car rotate past the apex, but now if I do that, it'll unload the inside rear and then it REALLY rotates after the apex!
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Old 07-07-2022, 07:42 PM   #28
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*If* on a compromise stockish or street/track setup, I'd say roll stiffness in general is what's lacking, not *front* roll stiffness specifically. Adding a stiffer front bar helps reduce roll, but exacerbates overloading of the outside front. On some cars/setups it might be a net positive for front grip, but IMO better to increase roll stiffness at both ends or just the rear of the car to reduce understeer. I went with Eibach front (softer setting, ~150% stiffer than stock) and rear (stiffer setting but also ~150% stiffer than stock), which worked pretty well. May still swap the stock front bar back in at Thompson next Fri/Sat if frustrated with understeer...
Motion ratio on the rear swaybar is significantly less then the front that attaches directly to the strut; 0.59 vs 0.92

You did in fact significantly increase front roll stiffness relative to the rear.
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