Any body have suggestions or stats on settings for front and rear Hotchkis sway bars. Four point front and three point rear adjustment. Stock suspension. Staggard Perreli AA traction rated tires. Run SCCA stock class. 2003 350Z 6 speed manual. Have test and tune coming up end of April.

 

Mine set at full stiff up front and in the middle in the back. Its easy enough to adjust and test.

 

IIRC I had mine setup at 3rd stiffest up front and middle in the rear, never did any racing like that tho

 

Back to basics:

More oversteer - higher roll stiffness in the rear

More understeer (reduce tail happiness) - higher stiffness in front

- That said, best way to tune your sway bars is start at what I call 0-0 or softest settings (hole #1 on both front and rear, close to end of bar). Drive it, get used to it, toss it a bit where safe (track testing, warm-up/practice sessions and ESPECIALLY your test and tune are ideal) and see how you like it. You will already feel a difference because at 0-0, the spring rate of the bars are already stiffer than stock.

- Next, analyze what you want the car to do better:

Do you feel the car is still rolling (body) and/or are your tires rolling too much? (Careful, that could just be tire pressure issues) - Try increasing both F&R roll stiffness to hole #2. Repeat above until happy about overall stiffness.

Now, time to really tune to your taste: do you want quicker turn-in/better rotation (disposition to oversteer) and a little more rear steer? Move only the rear bar mounting to next stiffer hole. Repeat testing as above (and you can continue that until you've maxed out the rear bar to full stiff but I don't encourage that as a soft front, full stiff rear will add significant oversteer and that can bite you on the butt if you're not careful.

OR... do you want to lessen the tendency to oversteer? (Bring it back to neutral or bias towards understeer). Leave rear bar where it was and only move the FRONT bar mounting to the next stiffer hole (inwards towards center of bar) and test again.

You see where this is going? You simply go back to the first two sentences and continue adjusting until you're satisfied.

For the record, the ideal "street/hills" setting FOR ME is Hole #1 (softest) front and Hole #2 Rear. This gives the car a little more turn-in with bias to oversteer. But that's just my setting for how I use the car.

Note for everyone: This technique works for any of the popular adjustable bars on the market. Eibach, Stillen, Hotchkis and others that use leverage (multi-hole mounting points) to adjust torsion rate on their sway bars.

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Not going to confuse the issue further at this point by talking about cross balancing - essentially setting not only F-R roll stiffness but also staggering the Side-to-Side stiffness to suit a particular track or a preference for right or left turns. Laff. But after you've set that up, be happy to explain how to do that if you think it needs some biasing side to side. (Most people don't and I'd hazard a guess, not many would know the difference. Racers who corner balance definitely do know the difference.

Hope this helps.

 

Hole 1 in the rear and stagger front front with hole 1 right side, hole 2 on the left.

Adjust stiffness and fine tune handling from there.

 

For the track full soft rear and full stiff front for most of the cars life, until I finally went stiffer bar in the front and stock bar in the back. I found that full stiff was the best front setting for most tracks up front, except for shorter/tigter/sweepier tracks, or if you are running a tire with greater than 200tw. In which case one of the medium settings may be best up front.

I have never, repeat never ever felt the need for more rear handling bias or rotation on this platform (without aero - caveat for the tracks I run and my spring rates and all that). Quite the opposite. And I can say that to be true for every suspension combo I have run, and I have tried lots and lots. The name of the game is to get the heavy front end to work as best as it possibly can first, and to get the most drive on as early as possible. In that order.

 

NOT arguing the point wth guitman32, terrasmak or anyone else but I find that interesting that such stiff front bias does so well on our platform (at least on track). Roll stiffness dictates which end's tires reach maximum slip angle first (and subsequently washes out beyond the tire's grip; before the other end). But it's totally logical as a track setting based on what guitman said in the last sentence quoted. I see that driver skill really comes into play there on a given track.... get the tires to maximum slip angle without exceeding the limit of tire grip. Interesting... need to try that. May or may not work for me and where I drive; but definitely worth a try!! Thanks, bud, that's informative!

Hmmmmmm..... he says, ponderingly. Mentally driving the two tracks local to me (Laguna, Sonoma), I guess neither really needs more rear steer other than maybe Sonoma's T7 and T11, Laguna's T2, all hairpins. But that much oversteer might help on turn in but mid-turn (second apex) and exit might be slower when the car requires too much opp lock correction. Hmmmmm.... great food for thought.

 

Believe me Ive wondered the same thing, so gave it a try. What I found when I took the H&R bar one step softer from full stiff on most tracks (it only has 2 holes) is that the front "felt" better, a little "freer" on entry, as you would expect. But the other consequence was that I couldnt get on the power as early. So I was slower. Conversely, the same experiment on a different, tighter twistier track (probably one of the worst tracks on tires in the country, PBIR) netted me a quicker time because its a track where the front end wants to wash away all the time, on almost all the corners. Same rear sway bar setting for all testing, full soft.

In the end its all a tradeoff; like a snowflake "correct" is different for everyone.

 

Thanks for response. does staggering holes apply to particular track turn direction (ovals) or works with road courses? Hope not a stupid question but, new to this.

 

guitman32 and MicVelo thank you for your info. I am brand new to this. You two are obviously way above my abilities but great info that I will be taking days digesting. Going to figure out bars on current tires. Was concerned with going too stiff for tires. I assume that is what you meen by washing out (traction loss). Will go to stickier tire compound later. You guys are running real tracks. I'm running amateur parking lot and small track runs. Lol. But, excellent info. I'm sure I will have alot more questions.Thanks again.

 

not a stupid question at all. The bar is a single spring that is balanced between the two sides. Every adjustment has an equal effect on the other side, so hole one is 20% stiffer, if hole 2 is 60% stiffer, a staggered setting would be 40% stiffer.

 

Really good thread... great question, excellent replies, and all the good info.

 

Makes sense but, that said would you get the same reaction if you changed that set up to hole 2 right, hole1 left. Does driver wieght (left side) have an effect on how you would stagger?

 

correct. Hole 2 right and hole 1 left is identicle to hole 1 right and hole 2 left.

Drivers weight matters for corner balance and when your setting adjustable endlinks

 

Thanks that answered my question for my common sense mind set, now I get it. Looked at adjustable endlinks but wasn't sure if enough improvement would be accomplished for my level of driving.( i.e. SCCA stock C class.) Plus don't want to get out of stock class....yet. Thanks again.