At the racetrack, conditions change constantly. The track may start slick and take rubber, or start tacky and dry out. Being able to make quick, effective adjustments is key to staying fast all day. This guide covers the most common track-side adjustments for quarter midgets and karts.
The Golden Rule: One Change at a Time
When making adjustments at the track, always change only one thing at a time. Make a small adjustment, test it, and note the result. If you change multiple things at once, you won't know what worked (or didn't work). Keep a notebook with your changes and the car's response.
Quick Reference Adjustment Chart
Use this chart as a quick guide for common handling issues. Detailed explanations for each adjustment follow below.
| Handling Condition | Adjustment Options (in order of speed/ease) |
|---|---|
| Tight (Push) - Won't turn | Increase rear stagger, reduce cross weight, increase RF negative camber, lower LR air pressure, move Panhard bar (shorten or raise) |
| Loose (Oversteer) - Rear slides | Decrease rear stagger, increase cross weight, reduce RF negative camber, raise LR air pressure, move Panhard bar (lengthen or lower) |
| Entry Tight (pushes entering corner) | Soften LR spring, add more front brake bias, add more front stagger |
| Entry Loose (oversteer entering) | Stiffen LR spring, reduce front brake bias, reduce front stagger |
| Exit Tight (pushes off corners) | Reduce cross weight, soften RR spring, increase rear stagger |
| Exit Loose (oversteer off corners) | Increase cross weight, stiffen RR spring, decrease rear stagger |
| Car bounces or hops | Adjust tire pressures, check shock rebound, check for binding suspension |
Track Side Adjustment Details
1. Tire Pressure Adjustments
Tire pressure is the quickest and easiest adjustment you can make at the track. You can change pressures between practice sessions or even during a race if you pit.
To Make Car Tighter (more push)
- Lower LR pressure: Increases left rear contact patch, adds grip
- Raise RF pressure: Reduces RF grip slightly, helps car turn
- Lower RR pressure: Adds rear grip, can help if loose off corners
To Make Car Looser (more oversteer)
- Raise LR pressure: Reduces left rear contact patch
- Lower RF pressure: Adds RF grip, makes car push less
- Raise RR pressure: Reduces rear grip, can help if tight off corners
Pressure Adjustment Range: Make changes in 0.5 to 1.0 psi increments. Always record hot pressures after a run and adjust cold pressures accordingly.
2. Stagger Adjustments (Tire Circumference)
Stagger is the difference between left and right rear tire circumference. It's a powerful handling tool, but changing tires or using tire treatments takes more time than air pressure.
| Change | Effect |
|---|---|
| Increase rear stagger (bigger RR or smaller LR) | Makes car looser (helps turn) |
| Decrease rear stagger (smaller RR or bigger LR) | Makes car tighter (reduces turn) |
Track-side stagger adjustment: If you have multiple sets of tires, you can swap left and right rears to make a big change. For small adjustments, you can use tire pressure (1 psi changes stagger by about 1/8").
3. Cross Weight (Wedge) Adjustments
Changing cross weight requires turning a threaded adjuster on a suspension link (usually left front or right rear). It's a bit more involved but still doable at the track with basic tools.
To Increase Cross Weight (tighter)
- Shorten left front link (pull LF down)
- Lengthen right rear link (let RR up)
To Decrease Cross Weight (looser)
- Lengthen left front link (let LF up)
- Shorten right rear link (pull RR down)
Tip: Mark your adjusters with paint or tape so you can see how much you've moved them. A 1/4 turn is a good starting point for a small change.
4. Panhard Bar Adjustments
If your car has an adjustable Panhard bar (height or length), this is another track-side tool.
| Adjustment | Effect |
|---|---|
| Raise Panhard bar (chassis or axle mount) | Higher roll center, more side bite (can make tighter) |
| Lower Panhard bar | Lower roll center, less side bite (can make looser) |
| Shorten bar (preload left) | Increases left rear bite, tighter |
| Lengthen bar (preload right) | Decreases left rear bite, looser |
5. Camber Adjustments
Camber changes are more time-consuming but can be done at the track if you have the tools. Shims or heim joints allow adjustment.
| Change | Effect |
|---|---|
| Add more RF negative camber | More corner grip (up to a point), can make tighter if excessive |
| Reduce RF negative camber | Less corner grip, looser |
6. Gear Ratio Changes
If the track is slick and you're struggling for traction, or if it's high-grip and you're running out of RPM, a gear change might be needed.
| Condition | Gear Change |
|---|---|
| Slick track, need more traction | Higher gear (smaller driver or larger axle sprocket) - helps acceleration |
| High grip, need more top end | Lower gear (larger driver or smaller axle sprocket) - increases top speed |
7. Spring Rubber (Spring Stiffeners)
Some racers carry spring rubbers (also called spring inserts or tender springs) that can be added to coils to effectively stiffen a spring temporarily.
- Add rubber to LR: Can help if car is loose entering corners.
- Add rubber to RR: Can help if car is tight off corners.
8. Shock Adjustments (if applicable)
If you have adjustable shocks, you can change rebound and compression settings. This is more advanced but very powerful.
- Stiffer rebound: Slows down suspension extension, can affect weight transfer.
- Stiffer compression: Slows down suspension compression, can make car feel tighter.
Track Side Adjustment Checklist
Here's a suggested order of operations for making adjustments at the track:
- Check tire pressures (hot and adjust cold for next session) - fastest and easiest.
- Adjust stagger via pressure or tire swap if needed.
- Make cross weight (wedge) adjustment - still relatively quick.
- Adjust Panhard bar height or preload.
- Change gear ratio if RPM is off.
- Change springs or shocks - more time-consuming, save for last.
Recording Your Setup
Keep a simple log for each track. Note:
- Date and track name
- Track conditions (slick, tacky, rough, smooth)
- Air temperature and humidity
- Tire pressures (cold and hot)
- Stagger measurements
- Cross weight percentage
- Any other adjustments made
- How the car handled (tight, loose, good)
Over time, this log becomes your most valuable tuning tool.
Summary
Track side adjustments are about reacting to changing conditions quickly and effectively. Start with the simplest adjustments (tire pressures) and work your way up. Always make one change at a time, and keep detailed notes. With practice, you'll be able to dial in your car in just a few laps.
For more detailed information on specific adjustments, see our guides on Basic Chassis Set Up, Cross Weights Explained, Understanding Stagger, and Panhard Bar Basics.