Learning how to tune suspension. Kindergarten level.
#22
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It really is a nice DD setup with my limited experience. I'm curious about a good AX setup. I realize I can throw money at it and get Xidas but I'm just nowhere near good enough to get a lot out of that quite yet, or so that's my understanding. I'll do some reading, this is another deep rabbit hole I know I'm getting into. It's gonna take a lot and a long time to get remotely competitive in SSM, but I wanna start honing in on a ball park setup for the next year or so. Holla holla spend dolla y'all.
#23
To get to the pointy end of a class like that you need to jump from below 400lb/in spring rates and long soft bump stops to 700/350 - 1000-550 lb/in range and invest in shocks that will control those rates.
This is where you'll find a lot of opinions, exida's are a proven commodity. Afco's are also an option, but no shock will be worth the money without the proper valving. In fact even lowly old Bilstein's with the right valving can kick some butt.
(Personal opinion alert) I've looked at the valving of hard s and MSM Bilstein's and calculated the critical dampening % and the low speed numbers look pretty decent up to 800/450 range. The high speed numbers are a little soft, so they won't be as good on rough tracks. A revalve by someone who knows what they're doing and I betcha they would be darn close to the high end stuff without adjustability. I'm running stock hard s shocks with 800/450 rates and the car does pretty darn good.
This is where you'll find a lot of opinions, exida's are a proven commodity. Afco's are also an option, but no shock will be worth the money without the proper valving. In fact even lowly old Bilstein's with the right valving can kick some butt.
(Personal opinion alert) I've looked at the valving of hard s and MSM Bilstein's and calculated the critical dampening % and the low speed numbers look pretty decent up to 800/450 range. The high speed numbers are a little soft, so they won't be as good on rough tracks. A revalve by someone who knows what they're doing and I betcha they would be darn close to the high end stuff without adjustability. I'm running stock hard s shocks with 800/450 rates and the car does pretty darn good.
#24
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"Pointy end" I like that haha. So you introduced me to a new term, valving. A google search later and my understanding is that valving is the size of the hole that allows the fluid to travel through (damping?) on compression and rebound, so the two parts of the assembly are the spring and the shock(?)... I'm figuring spring is for rebound and the shock itself controls the amount and rate of compression... am I right so far?
#25
Shocks are a deep rabbit hole that most people see as a black art because they don't have access to a shock dyno to be able to tune them. I can try till I'm blue in the face to explain it but this site does a much better job.
Autocross to Win (DGs Autocross Secrets) - Shocks
Autocross to Win (DGs Autocross Secrets) - Shocks
#26
I haven't done any research on your shocks but you might be able to retrofit them with sleeves to work with your springs. Whether it would be financially feasible is another thing, especially if you are considering getting new hardware. Having adjustable sleeves gives you the opportunity to get a real alignment and get your cross weights and hopefully side weights even, which makes for a more predictable/balanced handling car.
Re: rear bar, I always ran with the rear bar (can't remember NA6 or NA8 right now) back when the car was still early in development and the balance was fine. Since it is an autox car (CSP) and it was about 100#'s overweight and I refuse to get rid of the AC, certain things had to go and the rear bar was one of them. It saved 7#'s IIRC, but it was also the last place where you would want the weight to come off (low/behind driver). The balance obviously went to push and 50# heavier springs were added to bring the balance back. This in turn introduced sporadic wheelspin in a car that barely had 120 wtq. This was with Koni Race shocks and 6" 2.5 Eibach springs. When I switched to ARE Penske's, he sent me 400# springs for the rear and I immediately thought the car would push without a rear bar. I was dead wrong and even now with just over 130 wtq, no wheelspin ever.
So that big wall of text was just to say, you gotta try things and see what they do. And certain things are compromises while other things just compromise the wallet.
Re: rear bar, I always ran with the rear bar (can't remember NA6 or NA8 right now) back when the car was still early in development and the balance was fine. Since it is an autox car (CSP) and it was about 100#'s overweight and I refuse to get rid of the AC, certain things had to go and the rear bar was one of them. It saved 7#'s IIRC, but it was also the last place where you would want the weight to come off (low/behind driver). The balance obviously went to push and 50# heavier springs were added to bring the balance back. This in turn introduced sporadic wheelspin in a car that barely had 120 wtq. This was with Koni Race shocks and 6" 2.5 Eibach springs. When I switched to ARE Penske's, he sent me 400# springs for the rear and I immediately thought the car would push without a rear bar. I was dead wrong and even now with just over 130 wtq, no wheelspin ever.
So that big wall of text was just to say, you gotta try things and see what they do. And certain things are compromises while other things just compromise the wallet.
#28
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Well my thing is that I built the car with what seemed good and autocross was an afterthought. So i ended up in this class and figured i might as well try to have a car that can be near the others timewise
#32
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I am proud and confident to say my Benz would beat Philly's miata in autox; no question about it. My shocks tune themselves w/AGILITY CONTROL, it has more torque than is generated when your mom sits, and the 4‑ETS awd system would make a wrx fanboi cry. Hell, I could still be sipping my latte and listening to tunes via bluetooth from my phone through 11 speakers, all while running the heated seats.
hey gays, ever heard of 69? it was invented for a reason. sharing is caring.
#39
Wants to learn how to tune suspension and figure how changes "feel."
Goes to first ever auto-x on 215 tires.
Decides he needs 275 tires before the next auto-x.
Not quite the path I would have chosen. Maybe some 195s or 205s and a tunable suspension would have been a better place to start. Hell, no one has even mentioned alignment settings yet.
Goes to first ever auto-x on 215 tires.
Decides he needs 275 tires before the next auto-x.
Not quite the path I would have chosen. Maybe some 195s or 205s and a tunable suspension would have been a better place to start. Hell, no one has even mentioned alignment settings yet.
#40
Thanks guys! I appreciate the feedback. As a noob this is going to take time to learn but I'm gonna keep at it. After this thread I realized i have a couple more thousand dollars to spend to really tease out what the car is capable of, but that's probably over the next year. I'm in SSM because i think my built motor swap. It'll be turboed soon as well, so that'll be fun. I'm gonna check out those books.
Looks like the future holds: 275s and 11" wheels, Xidas or comparable, BBK, is lexan easy to work into a big spoiler? I'm having a ton of fun so far and have to learn how to drive this car. I wish more events were closer so i can try more. Getting 4 or 5 runs every few weeks isn't enough 😩 I ain't about that street recklessness
Looks like the future holds: 275s and 11" wheels, Xidas or comparable, BBK, is lexan easy to work into a big spoiler? I'm having a ton of fun so far and have to learn how to drive this car. I wish more events were closer so i can try more. Getting 4 or 5 runs every few weeks isn't enough 😩 I ain't about that street recklessness
I hope you don't plan on dumping all that into the car in one fell swoop. Stick with what you have and learn to drive it fast. Once you feel that you have exhausted all the adjustments to the car as is, then put money into making it fast.