I think I am regretting my spring selection
 

I ended up with 14k springs in the front. I am starting to regret it as I think it is too stiff, I probably should have gone with 12 and a big bar instead of 14. What do u guys think

Personally, yes. WO aero 14k is kinda stiff. The OEM setup has a wheel rate of about 167 in the front and 146 in the rear.That calculates out to a a ride frequency of about 1 with a 15% difference front/rear.

14K frontis 300+ wheel rate and a >=2.0 Hz ride frequency which is definitely above or at the upper limits of where a non aero sedan type car should be.

as a general guideline:
 0.5 - 1.5 Hz for passenger cars
 1.5 - 2.0 Hz for sedan racecars and moderate downforce formula cars
 3.0 - 5.0+ Hz for high downforce racecars

So unless you have a pretty significant splitter, you might want to tone it down.(Or buy a splitter!)

Check this link out
http://www.optimumg.com/docs/Springs...Tech_Tip_1.pdf

I violently disagree with the frequency guidelines above. You won't find a formula car with 1.5hz frequencies on planet earth. Most GT based race cars are 3hz+ and formula cars are over 4. 14k is not all that stiff in reality.

just curious, what about it seems "too stiff", also what dampers are you running?

Formula 1 no. Formula 5000, probably. I don't have specs on either one nor am I friends with any drivers from either one. But without Aero, I can not see any reason to use anything stiffer than 14K on a road course that has bumps, camber, and traction changes.

In a nice flat Auto X environment I can see the point. 14K spring with a corner weight of ~800 lbs is pushing the limit of tire compliance and would only be good on a very smooth flat surface-like auto X or tarmac. You will not be getting enough bump travel to ensure tire compliance. I don't know the math on bump stop rubbers, but proper bump stops is probably a better answer than 18K springs whether on tarmac or corner 6 of Big Willow.

Sorry man, but you are WAY out of alignment with what actual race cars use...

Even FSAE cars are well above 4hz.

Also, while most of the West Coast Auto-x sites are pretty flat...it's the opposite on the right coast. Our sites are mostly bumpy as ****...

Case in point:
http://farm6.staticflickr.com/5151/7...59a77ceb_c.jpg

waiting for the rest of the car's suspension specs before i give some input.
but in my opinion, a 370 on wide front tires at a good pace, 14kg isnt outta the question, but the damper needs to be up to snuff

Well then I apologize on believing in basic math. A small note though, if your front right tire is 8+ inches off the ground, you suspension is probably not tuned right and you need to reduce your spring rate. TY for proving my point with your photo demonstrating a terrible suspension.

I find this bordering on hysterical, but do carry on...

..it is "jacked" up because he hit a bump at 50mph while accelerating out of constant radius corner.

Same corner:
http://farm6.staticflickr.com/5444/7...30903ef0_c.jpg

Also, although I don't agree with Dennis Grant at all on set-up, he does supply an easy to use dynamics calculator on his website...

Autocross to Win (DGs Autocross Secrets) - Dynamics Calculator

Just out of curiosity, I looked up what a bog standard 996 GT3 cup car came with for springs....1200lb on front, with a strut.....on car with no weight on the front wheels. Then again, I am sure the fine folks at Porsche motorsport are just plain stupid and haven't discovered the internet knows all.

I'm just trying to think of that race where the winner had two wheels off the ground. Oh yeah now I remember, the Dukes of Hazard, those guys were fast! I bet they were using like 5000Hz wheel rates to get away from Boss Hog!

You must not watch any touring car racing....

Umm that's not a touring track on television, that's a parking lot with cones.

I give up, bro. Whether the math make sense in your head or not, no one that wins anything of note runs frequencies within your above guidelines....period. No open pro GT series is going to have cars even close to 2.5hz or lower. It's just fact.

I should also mention, my car is considered "soft" by most, and I run about 2.3/2.15hz.

Should also mention that clintfocus is absolutely right on how front tire size and compound plays into things, but even if it were a 255 RS3 or the like, I would want 1.9-2hz up front, at a minimum without aero.

He's on Fortune Auto 510's

all hz's aside, just from my ricer math, a car with something like 275-285 up front, like what i run, even on a entry level r compound, 14kg is what id put up there no hesitation, and that's still on the compliant side for the bumpy socal tracks. but if the dampers dont do there just the car will get unsettled, which more so may be Cossie's issue with those Fortune's (no offense).

the day i DO run something like that up front, ill be on a custom valved KW, or a JRZ double adjustable damper.

I haven't put it on the car yet. I was just thinking I should have done 10 or 12k with a big sway bar instead of 14k with stock bar. The shocks are supposed to be build for the springs, which is more of a build than any off the shelf items i can buy. I hope to get everything installed this weekend so I can try it at Laguna Seca as I had already established a baseline there last month.

http://imageshack.us/a/img203/1350/dw8m.jpg

http://imageshack.us/a/img268/219/bs6p.jpg

wait you havent tried them yet? dude it'll be fine LOL

been working like crazy and i have no time, need to do it this weekend, about to set the preloads tonight

I used custom double motons last couple of years, but I am switching to Penske for 2014. I've gone as high as 1200lb on the front of my car, but while it transitions great (315 Hoosier A6's), the point of diminishing return overall is right around 1000lb on front. Anything over 1000lb, again while better on transition, sacrifices in sweeper grip. That said, part of that was not having quite enough camber as well. Unless something has changed, the major issue with KW is that they won't custom valve anything until you get to the motorsports line, which has very little following in the U.S. They certainly are not a poor product, though.

Terry from fortune auto recommended me these...

Hello Scott,
Based on your intended usage and vehicle, I would recommend:
15k front and 13k rear spring rates.

:tup:

I hope that 13k isn't in coilover form...?

I'm sure it is. 510's

And sorry, not trying to be a jerk. I think we prolly agree more than disagree here. Any full on race car yes is going to be 2.5+ . With a daily driver, yes I think what you are suggesting is true as well-2.3 is about the upper limit of what is usable wo rattling your teeth out driving to McDonalds. The front to back split is what I think is ultimately important. My only point I was trying to get across is that at 14K, I think there is a threshold based on the weight of this car. That's it.

i have some connections with KW so if i needed something valved i could get it ;) same with JRZ.

Cossie do you drive or trailer to Laguna Seca? I thought you were towards Orange County? I want to get up there but not willing to drive the whole way-need to buy or rent a trailer.

I trailer my tools and tires to laguna, I live 90 miles from it

/Jealous

I want to go to that track so bad, but not willing to risk a 5 hour tow. Do you go to Button Willow?

I was at Buttonwillow when one of the club wouldn't let me go to Sonoma due to me being new to that track (I was fine when i went a month later). Buttonwillow is nice, but it doesn't have the "it" factor and it honestly cost me just as much as Sonoma and Laguna once you factor in travel. Also with a baby, dogs and wife at home, I am probably only going to do Sonoma and Laguna only. It's not worth the extra 5 hours I have to drive.

I did put on the rear coilover, took me forever as I wanted to do it right. Setting the height and preload properly took forever. I did take it for a quick spin after. On flat surface, car seems to behave fine. On bumpy road, you can really feel the stiff springs in the back. I hope the fronts are easier to do, I am this close from just calling the shop to have them to do it. Arggg.

$hit. Freaking bolt for the lower front shock froze, I can't change the stupid thing arggg.

Btw, should I get a front sway bar too?

Soak in penetrating oil overnight and get a bigger impact/breaker bar.

When I changed my front stock sway bar links for the SPL's. The stock links was hard to break free. I put a wrench on the link stud and a big breaker bar with 6 point socket on the nut to loosen it. ;)

My front passenger bolt was froze on mine. Beat the hell out of the bolt, soaked overnight with pb blaster and it wouldnt budge. I had to result to a bolt extractor and my neighbor let me borrow his air impact wrench. My 450 ft lb wouldnt get it done but his 900 ft lb made quick work or maybe it was loosened up. Good luck on this task. The nut was $2 at my local dealer.

I went 12k fr and 10k rr spring rate for my setup so curious to what you think once you test out your setup.

I made the mistake of not having a 6 point 19mm. The shop will install the last two at $150

I think you will eventually want one. But I want to say drive the car before you do anymore. Adding more stuff will just confuse you as to what has changed. Try the new springs and ask yourself how it feels on entry, how is it mid corner, what happens when you power down on exit. Don't fix what isn't determined broken yet.

However just based on what guys like Clint and just about what everyone else suggested before, you will probably want to end up running a stiffer front bar. Take your time with it though. You are the ultimate decider on whether it needs one or not.

No one stocks it, I am gonna go with the coilover for now. I probably won't even change the pads, I figure it will be cold

I got everything installed. I paid $150 to get the two fronts installed. I am planning to take it into a speedshop to have it cornerweight and realign this Friday. Since I had to rush home after I pick up the car, I was only able to put 6 miles on the suspension. With the front being at 1/3 soft and the back at 2/3 soft, I found the ride to be very comparable to stock. If you rate the stock ride being a 3, this only made it a 2.5 or maybe a 2. The difference is very small. As far as how it drives, I honestly don't have enough miles or hard drives to know what the true difference is. Based on what I could feel, I can tell you to save your $2000 and just invest in a sway bar instead as the car still rolls. The new coilover did make the better in transition, but it didn't really make the car lean much less nor did it dramatically increase its responsiveness. I am going to go back out later tonight to see what I can find, but it's been disappointing so far given the money spent on it. My original goal was to go two seconds faster than my last track day, but I just don't see it happening with the way the car is.