New to the southerns eh? Well you came to the right place. I would start off with springs as follows:
LF 600 RF 550 LR 175 LR 150
Ride heights are a bit trickier. You want the center bolt that goes through your a-arm (attaching a-arm to the chassis) to be even with or slightly below the center of your lower ball joint (the ball part not the shaft). this should be somewhere around 8" both sides. I always liked to have the left side 1/4" higher than the right that way when the driver gets in the ride heights are even.
For the rear we run 1-1.5" above the front. This in combination with the soft rear springs will allow the rear of the car to rock down creating more forward bite. You typically want to run as much lower rear trailing arm angle as you can (like a modified) which will help with downforce on the rear end.
Try to set the car up like this and let me know what you think. I always like to run a lot of left rear in the car to keep the car loose on entry and tight on exit but that's more of a driver preference when it comes to southerns.
I have won a state championship in a southern and have raced them for quite a while. I don't mind helping share set up advice with new drivers.
If you have any other questions let me know. When you are ready for shocks I found some pretty trick stuff that I wont mind sharing as well!
Where I used to run it was probably the slickest track in the country. This is a good basic dryslick set up. If you need more bite I would recommend going with 150's across the rear. What is your setup now? wheel weights, ride heights, percentages, offsets etc.?
Hi guys I’m Looking for a generic guide to making changes to setup. Basically what changes do what and when the car is acting a certain way what changes could be made to help. Is there anything like that out there? TIA
lilsneeaky7, these are general rules of thumb for a dirt circle track chassis that have worked for me....
Most cars have a higher rear percentage so the rear tires have a larger influence on dynamic chassis handling characteristics.(dynamic meaning, "as the car is entering and exiting the corners)
1)increasing LR bite (more wedge), frees car on deceleration and tightens on acceleration (gives the LR more control, more braking power and more drive off the corner) 2)decreasing LR bite, (less wedge), tightens car on deceleration and loosens on acceleration (gives RR more control, more braking power and more drive off the corner)
Think of your rear tires like your Zero turn lawn mower or a bulldozer....
Example: (LR has more control) pull back on the left stick (simulating braking) it goes left, push forward on the left stick (simulating on throttle) it goes right.
Same goes for the RR having more control, pull back on right stick (simulating decel) it goes right, push right stick forward ( simulating on throttle) it goes left.
The trick is to find the balance of the rear tires during deceleration and acceleration. It's all a balancing compromise.
(Changing Right side springs will usually effect "dynamic" wedge on entry and exit)
3) increase RF spring rate helps keep "Dynamic" wedge/bite in the car when it is going through the corner, this will free the car on decel and tighten on accel (helps LR have more control, more braking grip and more acceleration grip) 4) decrease RF spring rate reduces wedge/bite when the car is going through the corner, this will tighten the car on decel and loosen on accel (helps RR have more control, more braking and more acceleration grip) 5) stiffen RR spring reduces dynamic wedge while going through the corner, this will tighten on decel and loosen on accel (gives RR more control on braking and acceleration) 6) soften RR spring loosens deceleration, reduces RR control on braking
Are you starting to see the pattern?
Now LF spring is a little different, it will generally be a more noticeable change on decel.
7) soften LF spring loosens car on decel, allows the RR to unload during decel reducing it's control on decel 8) stiffen LF tightens car on decel, keeps the RR loaded during decel
The LR spring reacts differently also, I will try to explain how the spring functions so that you will understand how it has an effect on dynamic wedge ( I will use extreme examples of LR springs to help paint this picture )
First you enter the corner (you are decelerating and turning, car rolls forward and to the right) loading the RF spring. This in turn unloads the LR spring (we will say 2") If you have a 300lb spring, you will lose 600lbs of load on the LR tire. If you have a 100lb spring, you will lose 200lbs of load on the LR tire.
The 100lb spring still has 400lbs more load during decel and when you start to accelerate. Are seeing the picture that I am trying to paint here?
9) soften the LR spring keeps dynamic wedge in the car, giving the LR more control, Loosens on decel and tightens on accel. 10) stiffen the LR reduces dynamic wedge during cornering, therefore reducing the grip level of the LR tire, tightening on decel and loosening on accel.
Now to weight placement and when to move it. Keep it simple.
11) Moving weight back helps overall traction of rear tires during deceleration and acceleration. 12) moving weight forward helps overall traction of the front tires on decel and accel. 13) weight to the left helps left side traction 14) weight to the right helps right side traction
Weight transfer. Don't over think this part, it's just physics. Hit the brakes, weight moves forward. Turn to the left, weight moves to the right. Hit the gas, weight moves to the rear.
Weight height dictates how the weight transfers through the chassis and the springs.
15) raising the weight will create more chassis "roll". this means that you will unload weight off of a pair of springs and load a pair of springs, during the weight transfer process. (hit the brakes, the transferring weight unloads the rear springs and compresses the front springs. this give more traction to the front tires and removes it from the rear) (turn to the left, the transferring weight unloads the left springs and compresses the right springs. this give more traction to the right side tires and removes it from the left)
Raising the weight is done for tracks that are slow through the corners or as the track gets slick (which means that the speed through the corners has slowed down)
16)Lowering the weight slows down (reduces) the transfer of weight through the springs.
Generally: The more corner speed you have the lower the weight height. The slower the corner speed, the higher you will want to place weight.
Now there are MANY variables that play a roll into how much these changes effect the handling of the car. Track size, track conditions, driving styles, front end geometry, rear geometry, car weight, tire size, tire compounds, wheel offsets..... the list goes on.
This is just a basic, keep it simple, baseline approach to get a car competitive.