STX setup sharing thread (2021)

[Locust]

Originally Posted by Autoenthusiastasm

Question on alignment. 8k for spring rate. -3.5 front, -2.5 rear. +.05 toe front. My car seems to push a bit on turn in. Is this a result of + toe, my 22mm sway. Too firm on my coil overs. Running on pavement. I had requested neutral toe, but the tech said this is recommended

Your toe is backwards and 22mm is on the high end of setups.

[steverife]

Originally Posted by Autoxer62

I finally have a starting setup (of sorts):

- GReddy/KW V2 coilovers 6k/7k (336/392)
- Karcepts front bar, full soft
- RPF1 17x9 +35
- 255/40-17 RT660
- Camber 2.5F/1.8R (limited by the top hats) 1mm toe F/R

Nothing fell off or made any strange noises on the test drive last night so I signed up for a local Saturday, we'll see how I do, it's been a while.

--Bryan

That color is beautiful.

[Autoenthusiastasm]

Originally Posted by Locust

Your toe is backwards and 22mm is on the high end of setups.

Should I consider the 19 mm front? Perrins. Will toe
out slow my turn in.

[Autoxer62]

Generally toe out in the front makes the car want to turn (all the time).

[AFRichZC6]

Your current alignment settings shouldn't cause you too much issue with turn-in. Maybe not ideal but also not a major contributor to the corner entry push. Toe-out would typically quicken turn-in response.

Let's assume it's the setup and not from driver input. What tires are you on, and is the road surface concrete or asphalt? How much shock travel do you have up front in bump/compression? Do you have bumpstops installed, and are they being engaged too soon? Maybe remove, replace with softer ones, or trim them down. The combination of your front spring rate and ARB could be too stiff for the tire/road surface. If your front ARB is adjustable, set it softer.

[Autoenthusiastasm]

Originally Posted by Autoxer62

Generally toe out in the front makes the car want to turn (all the time).

Car is stable on highway,it does not seem darty. I’m guessing my delayed turn in is more likely driver error with throttle or overly stiff front sway.

[Breezio]

Originally Posted by Locust

Your toe is backwards and 22mm is on the high end of setups.

Strange, last I saw, most people were running a 22mm FSB in STX...

[G_Ride]

Originally Posted by Autoenthusiastasm

Should I consider the 19 mm front? Perrins. Will toe
out slow my turn in.

I'm not sure which 22mm swaybar you have, but I assume it's adjustable. Have you tried a softer setting?

[Autoenthusiastasm]

Originally Posted by G_Ride

I'm not sure which 22mm swaybar you have, but I assume it's adjustable. Have you tried a softer setting?

It’s the Perrin 22 at full soft

[G_Ride]

Originally Posted by Autoenthusiastasm

It’s the Perrin 22 at full soft

Like AFRichZC6 said, it could be the combination of your front spring rate and swaybar could be too stiff for your surface.

I run 6k front/9k rear springs and the 22mm Perrin front bar at middle setting (one side on stiff, one side on soft). Turn-in is pretty good, but I also have -4.5 degrees of front camber (zero toe) and run on very grippy, tire grating concrete.

[Autoenthusiastasm]

Originally Posted by G_Ride

Like AFRichZC6 said, it could be the combination of your front spring rate and swaybar could be too stiff for your surface.

I run 6k front/9k rear springs and the 22mm Perrin front bar at middle setting (one side on stiff, one side on soft). Turn-in is pretty good, but I also have -4.5 degrees of front camber (zero toe) and run on very grippy, tire grating concrete.

I ran my first national event this weekend and asked lots of questions. About fixing understeer. I could put a softer spring in front. Decrease air pressure in front, and or raise rear air pressure. Decrease stiffness of my front coil overs. . I’m still trying to figure out air pressure fit my Yokohama’s. Some say I can go real low, some say they work regular pressure. The guy who schools me puts them at 35.

[Breezio]

Originally Posted by Autoenthusiastasm

I ran my first national event this weekend and asked lots of questions. About fixing understeer. I could put a softer spring in front. Decrease air pressure in front, and or raise rear air pressure. Decrease stiffness of my front coil overs. . I’m still trying to figure out air pressure fit my Yokohama’s. Some say I can go real low, some say they work regular pressure. The guy who schools me puts them at 35.

245/255 yoks at 35psi? That's way high compared to anyone I know. I run 29 front 28 rear with 255's and -3.8 camber in front.
My buddy is at 27 front 25 rear for his 245's and a bit more camber up front.

[AFRichZC6]

Originally Posted by Autoenthusiastasm

I ran my first national event this weekend and asked lots of questions. About fixing understeer. I could put a softer spring in front. Decrease air pressure in front, and or raise rear air pressure. Decrease stiffness of my front coil overs. . I’m still trying to figure out air pressure fit my Yokohama’s. Some say I can go real low, some say they work regular pressure. The guy who schools me puts them at 35.

Here is my methodology. You want to lean towards making your suspension setup work for your tires rather than your tires work for your suspension setup. A tire and wheel combo have a range of tire pressures and a range of camber (at the tire) that is optimal for grip. Keep in mind that sometimes what is best for grip may not always be best for wear, and the tire may not wear evenly. You'll want to set up the suspension to help the tire work at its best for the type of driving you're doing. We're not in Street class - we can change a lot more in the suspension.

Generally speaking, if you are increasing tire pressure beyond what is optimal for the tire and wheel to compensate for unreasonably uneven wear/temps due to lack of camber, then you should find ways to add camber in the suspension. If you are decreasing tire pressure beyond what is optimal for the tire and wheel to try to get more grip because your suspension is too stiff and overloading the tire (consider road surface), then you should soften your suspension (spring rate, ARB). If you are loading the tire too quickly or not quickly enough (again, consider road surface), then you change your damper settings.

[Autoxer62]

I too would drop the pressure to 30 and see how that works. You also might try braking a little earlier and see how that affects the understeer.