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Discussion Starter · #1 ·
I know there are a lot of threads discussing spring rates. However, I havent seen any mentioning the spring rates that I am seeing would be the best fit for me and I'm wondering exactly why that is.

I havent had my car corner weighed, but I have seen corner weights for one that was pretty close to how I'd have mine set up on a track day. I will absolutely get my car corner weighed before I buy the coilovers/springs, I'm just estimating right now so I can find any errors in my thought process beforehand.

LF: 971 RF: 969
LR: 597 RR: 600


I know the motion rate is 1 in front and 0.7 in the rear. I've been using this to calculate my spring rates: Spring Rate Calculator

I've also been using a 2.70-2.75 GHz suspension frequency and I came up with 13kg/mm (728lb/in) front and 14kg/mm (784 lb/in) rear spring rates.
I havent seen anyone else with even close to these same numbers and I'm wondering if that's because I've miscalculated or just that others dont want the ride to be that rough.

I basically want it to be a full on race car. It's currently my daily, but once I get a different car, itll be backroad/track only.

I plan on putting 17" rims on as well because of how much lighter they will be. So it will be half an inch lower because of this. Will this affect my spring rates in the way of "every 1" lower needs 1.5x stiffer?"


For reference, these (YCW Reference Edition) are the coilovers I'm getting and you can custom order spring rates along with them.
 

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A lot of it would have to do with being compliant on the streets, and with those rates, they would be fairly stiff even with very good dampers (I'm running 10k front and 12k rear but my car is primarily an autox car that needs compliance as it is driven to and from events, even national ones).
If you are going to be using the car strictly for track, those rates would be great especially if you plan on running something like a Hoosier for rubber.
 

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Discussion Starter · #3 ·
A lot of it would have to do with being compliant on the streets, and with those rates, they would be fairly stiff even with very good dampers (I'm running 10k front and 12k rear but my car is primarily an autox car that needs compliance as it is driven to and from events, even national ones).
If you are going to be using the car strictly for track, those rates would be great especially if you plan on running something like a Hoosier for rubber.
I didn't realize there was a certain maximum stiffness for a car to be compliant for road use (safety inspection, I'm assuming?) If it is safety inspection thing, idk about any other state, but in missouri you dont need a safety inspection for 10 years now lol and I'd probably be running full race tires once I get my new car because I'll only be driving it when it's not raining or at the track lol
 

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I didn't realize there was a certain maximum stiffness for a car to be compliant for road use (safety inspection, I'm assuming?) If it is safety inspection thing, idk about any other state, but in missouri you dont need a safety inspection for 10 years now lol and I'd probably be running full race tires once I get my new car because I'll only be driving it when it's not raining or at the track lol
By compliant, I meant bearable to drive under normal driving conditions, i.e. imperfect road surfaces, etc.
 

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Discussion Starter · #5 ·
Oh yeah I mean I ride my motorcycle every chance I get and I'm always sore after 30 minutes and I continue to ride for hours. Cant be much worse than that and even if it is, I'm young lol yolo
 
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