Odd experience on a mountain run.

wtb6mtv8rwd

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As been said, add negative camber and wider/stickier tires.





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Bluemustang

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As been said, add negative camber and wider/stickier tires.
Square wheel/tire setup will help too. These cars are heavy, especially up front and poor camber curve there also. It needs at least 275 or 285 wide and -2ish camber to turn and grip. Square up the tires and do the alignment and watch your understeer go away I bet.

Edit: Also would like to add: I ran even camber front/rear for a couple years. I found by running 0.5 degree less negative camber in the rear helped the car to rotate. It was quite a dramatic change actually. It was enough to move the balance from understeer to oversteer. I then lowered the rear tire pressure by 2 psi and that eliminated the rear stepping away too easily at slow speeds and turned mid speed corners (~60 mph) to a slight tail wag at the limit. Stiffening the front bar will most likely perfect the balance. But main point being don't underestimate alignment in the balance behavior. It might have more effect that you think. -2 F/ -1.5 R, 0.00 front total toe, 0.12 per side rear toe would be my recommendation for "spirited" Street driving. The car needs more camber than you think when you really start pushing it. Ford's factory alignment is backwards.
 
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wtb6mtv8rwd

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^ No smidge of toe in up front?
 

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^ No smidge of toe in up front?
For road manners maybe, but not for performance unless you prefer a more lazy turn in response. I've tried a few interations of slight toe-in and always preferred it at zero, personally. It can make the steering more twitchy but that's easily solved by an adjustment - avoiding making too many frequent corrections. It's personal preference really.
 

wtb6mtv8rwd

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Don't mean to hijack OP's thread. I'm getting an alignment tomorrow on mine.

Main goal beyond handling and grip (which the PP2 has plenty of) would be reasonable tire wear. I do a fair bit of mountain carving and as delivered the tires have been wearing more on the outside. The car doesn't have enough camber stock.

On previous relatively heavy front engine rear drive cars (with macpherson struts) I'd go -3, 0 toe front and -2 slight toe in rear. Worked well. I realize alignments aren't one size fit all but I was also looking at the '19 GT350R "track" settings (attached) and noticed it calls for a little toe in up front. Wasn't sure whether to go with that or not on the S550 platform.

Screen Shot 2020-10-19 at 1.10.12 PM.png
 

Bluemustang

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Don't mean to hijack OP's thread. I'm getting an alignment tomorrow on mine.

Main goal beyond handling and grip (which the PP2 has plenty of) would be reasonable tire wear. I do a fair bit of mountain carving and as delivered the tires have been wearing more on the outside. The car doesn't have enough camber stock.

On previous relatively heavy front engine rear drive cars (with macpherson struts) I'd go -3, 0 toe front and -2 slight toe in rear. Worked well. I realize alignments aren't one size fit all but I was also looking at the '19 GT350R "track" settings (attached) and noticed it calls for a little toe in up front. Wasn't sure whether to go with that or not on the S550 platform.

Screen Shot 2020-10-19 at 1.10.12 PM.png
I can't speak to the toe in. But I am basically running that alignment now. Spring rates similar to GT350R (BMR handling springs, Ford Performance dampers). I'm not running quite as much toe as they are calling for, but it feels great..

-2.2 front camber, 0.00 toe
Caster 6.9
-1.7 rear camber 0.20 toe.

Works extremely well for back roads at higher commitment levels.
 

NightmareMoon

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Y'all coming in with the mechanical changes....

90% of the time its driver mod. Don't brake too late into the corner or it will plow. Need to be letting off the braking just as or just before you're adding steering or you'll overload the front outside tire. Adding MORE steering after that just causes it to wash out more.
 

wtb6mtv8rwd

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I can't speak to the toe in. But I am basically running that alignment now. Spring rates similar to GT350R (BMR handling springs, Ford Performance dampers). I'm not running quite as much toe as they are calling for, but it feels great..

-2.2 front camber, 0.00 toe
Caster 6.9
-1.7 rear camber 0.20 toe.

Works extremely well for back roads at higher commitment levels.
:thumbsup:
I guess between 0 toe and half a degree in per side I'd be really splitting hairs either way.

How's your tire wear?
 
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Y'all coming in with the mechanical changes....

90% of the time its driver mod. Don't brake too late into the corner or it will plow. Need to be letting off the braking just as or just before you're adding steering or you'll overload the front outside tire. Adding MORE steering after that just causes it to wash out more.
this is crucial, with no background being explained that the right answer. As for my back ground I haven’t done anything with my GT yet, however my old ST’s have been around Road Atlanta, AMP, and VIR with a couple BMW experiences at RA with instructors. Basic car dynamics I know ok. My understeer incident this past weekend could have been much worse with someone inexperienced and panicking. The turn was a decreasing radius, I went in with a little trail braking easing off the brakes as I entered the sharper section, and the car plowed. At that point target fixation could easily occur, or standing on the brakes which would have resulted in a cliff face. Instead I gently gave some throttle to transfer weight off the nose and get the car to rotate some. The guys behind me said it just looked like the rear came out mid corner. They didn’t know what actually was happening.
 

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Understood. My 2c is that it could still be a bit of driver induced thing. You have a decent amount of FWD experience, but RWD takes practice too.

That said, (as mentioned by others) the car does have a typical factory bias to understeer. It won’t dance nicely as delivered. I vaguely remeber this as being a dead spot dominated by /mild/ understeer until you really man handled the car into oversteer (usually with with too-much throttle). Completely washing out is likely driver error tho. You took slight understeer and added more steering angle, or perhaps hit the debris that always lives on the center stripe between lanes?

On my 16 GT a slightly stiffer rear swaybar and a good alignment (including mods for a bit more front tire camber) cured the factory balance issues and removed the dead spot between understeer and oversteer. Wider front tires came later but the above was enough to fix the majority of noticeable factory understeer.

there are other mods to improve front grip (larger front tires, better dampers), and all sorts of other ways to sharpen up the handling, but a complete washout of front traction means you Very likely asked to much with your inputs for the road conditions.

For a humbling example, I just spent two days at a championship tour autox driving a car with one front shock set on full stiff and the other set on full soft (unbeknownst to me at the time). The last run of the last day I had a massive washout understeer causing me to drop from 1st to 3rd in my class. I don’t blame the shock settings, I know I botched it and came in too hot to slow the car and also carve the turn. If the shocks contributed it wasn’t nearly as much as my own driving. Any smaller understeer I would and did correct with smaller inputs by feel before it got so bad to put me out of my “lane”
 

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To put it more simply - if the car does something that surprises you, thats a driver training or familiarity issue.

If the car consistently does something that you don’t like, that could be car setup issue (or also still could also be a driver habit, it depends)
 

TeeLew

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Y'all coming in with the mechanical changes....

90% of the time its driver mod. Don't brake too late into the corner or it will plow. Need to be letting off the braking just as or just before you're adding steering or you'll overload the front outside tire. Adding MORE steering after that just causes it to wash out more.
Ya, I was thinking the same thing. Unless the pace was really at the limit and your buddies are legitimately fast drivers, it's mostly a matter of user error.

If the pace really was that fast, though, then you're all morons.
 

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this is crucial, with no background being explained that the right answer. As for my back ground I haven’t done anything with my GT yet, however my old ST’s have been around Road Atlanta, AMP, and VIR with a couple BMW experiences at RA with instructors. Basic car dynamics I know ok. My understeer incident this past weekend could have been much worse with someone inexperienced and panicking. The turn was a decreasing radius, I went in with a little trail braking easing off the brakes as I entered the sharper section, and the car plowed. At that point target fixation could easily occur, or standing on the brakes which would have resulted in a cliff face. Instead I gently gave some throttle to transfer weight off the nose and get the car to rotate some. The guys behind me said it just looked like the rear came out mid corner. They didn’t know what actually was happening.
I drive my PP GT on mountain roads with a few friends that drive Evo X cars so to be able to drive with there pace is a challange however at the moment my car is neutral in balance so no Understeer or Oversteer of any kind. How I get that: Strut tower brace (not available in europe), Steeda front swaybar on full soft, Steeda Camber Plates and an agressive allignment (this made the most difference) -1.4 camber all around 0.20 toe in front and -0.20 toe out rear (this helped the rear to stop stepping out).

With this on my last mountain pass drive my car was on the tail of the Evo X's and was super fast and fun to drive.
 
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CorvZ061

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To put it more simply - if the car does something that surprises you, thats a driver training or familiarity issue.

If the car consistently does something that you don’t like, that could be car setup issue (or also still could also be a driver habit, it depends)
I definitely don’t discount driver error, first run in a car with 2500 miles, there’s going to be familiarity issues. The guys I went with know the roads very well, I don’t. They claim their cars are ‘dialed’ and maybe they are, or maybe they’re just dumb for trying to push that hard on public roads, you decide.

After getting my nerves back under control after the first unexpected time I started pushing a little more in those tight parts and in a more ‘controlled’ way was able to replicate the understeer every time, even when coming into the turn completely neutral, with no power or brakes. I moved to the back of the pack and went at my own pace and had a lot of fun, but in no way able to keep up with them, just met up at the various planned stops.
 

Michael_vroomvroom

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I drive my PP GT on mountain roads with a few friends that drive Evo X cars so to be able to drive with there pace is a challange however at the moment my car is neutral in balance so no Understeer or Oversteer of any kind. How I get that: Strut tower brace (not available in europe), Steeda front swaybar on full soft, Steeda Camber Plates and an agressive allignment (this made the most difference) -1.4 camber all around 0.20 toe in front and -0.20 toe out rear (this helped the rear to stop stepping out).

With this on my last mountain pass drive my car was on the tail of the Evo X's and was super fast and fun to drive.
I'm saving your post to read up further on what the things you are saying mean at a later point.

I've started tracking my car too (fourth trackday coming up in two weeks), to learn my car and how to drive it better, but I have not started reading or thinking about the things you mention yet, as I'm sure "driver mod" is so much more important in my case.

Because there are some nice mountain roads here too, what you wrote made me think that what you are saying could be relevant for me even now, off-track, though. Should you or anyone else care to elaborate a bit for a newbie, that'd be really nice too.
 

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