Stop Bouncing and Spinning: GT4 Kerb Technique That Works

Learn How To Take Kerbs With The Ford Mustang Gt4 in iRacing—what kerbs to attack, what to avoid, and drills to stay fast without killing tires.

Kerbs in the Mustang GT4 can feel like a coin flip: sometimes you gain time, sometimes the car pogo-sticks wide, upsets the rear, and you’re collecting 1x’s (or worse) all the way down the next straight. You’re not imagining it—the Mustang’s front-engine weight and “big car” inertia make sloppy kerb use show up louder than in some mid-engine cars.

In this guide you’ll learn How To Take Kerbs With The Ford Mustang Gt4 in a way that’s fast, consistent, and kind to your rear tires, plus what to change in your approach when you jump into the FR500S or iRacing Mustang GT3 / Dark Horse.

Quick Answer: In the Mustang GT4, treat kerbs like a precision tool, not free asphalt. Avoid hitting tall “sausage” kerbs or taking kerbs while heavily braking or heavily accelerating. Aim to ride flat kerb with a stable car (either light maintenance throttle or neutral), take kerbs with one side of the car at a time, and prioritize exit stability over “hero” apex cuts that cost you traction and rear tire life.

How To Take Kerbs With The Ford Mustang Gt4

Kerb technique is really about one thing: managing weight transfer (how the car’s weight moves forward/back/side-to-side) so the tire contact patches stay loaded smoothly.

In the Mustang GT4, kerbs matter more because:

Front-engine mass + inertia: when the car gets bounced, it doesn’t “float” back into line quickly. It keeps moving in the direction it was upset.
Entry stability is good… until you ask for rotation on a kerb: if you try to rotate the car and climb a kerb at the same time, you’ll often get either understeer (front slides wide) or snap oversteer (rear suddenly steps out).
Rear tire management is everything in GT4: kerb strikes often turn into wheelspin on exit, and wheelspin is basically you paying lap time and tire wear.

A few quick definitions (so we’re speaking the same language):

Trail braking: gradually releasing brake pressure into the corner to help the car rotate.
Rotation: the car turning into the corner (yaw).
Understeer: front tires slide first; car won’t turn.
Oversteer: rear tires slide first; rear steps out.
Snap oversteer: sudden oversteer that’s hard to catch—common after an abrupt grip change (like a kerb).
ABS: anti-lock braking (helps prevent full lockups).
TC (traction control): reduces wheelspin on throttle.
Slip angle: the difference between where a tire points and where it actually travels; a little is fast, too much is sliding.

Step-by-Step: What to Do Next (Kerb Method You Can Repeat)

Use this as your default process in practice, then refine per track.

Classify the kerb before you attack it
- Flat/painted kerb (low profile, often safe): usually attackable.
- Tall/stepped kerb (big ridges): “respect it.”
- Sausage kerb / high inner nub: treat as a wall you can drive over once (and regret).
Rule of thumb for the Mustang GT4: if the kerb can lift a tire noticeably, it can also trigger ABS weirdness, upset the rear, or bounce you into a 1x/off.
Pick the phase: brake, rotate, or drive—don’t do all three on the kerb Kerb hits are safest when the car is in a stable state:
- Best: light maintenance throttle or neutral (very light brake or no pedal).
- Risky: heavy trail braking on the kerb (front load + bounce = understeer/ABS chatter).
- Also risky: big throttle application on the kerb (rear unload + wheelspin = snap).
Approach with a “one-side-at-a-time” mindset Instead of putting both inside tires over the kerb abruptly:
- Let the inside front touch first, then the inside rear.
- Avoid slamming the whole inside of the car onto the kerb at once—this is where the Mustang feels like it “falls” onto the outside tires and pushes wide.
Use the kerb for placement, not for rotation In the GT4 Mustang, you generally want:
- Rotation to happen just before the kerb (on smooth asphalt).
- The kerb to be a guide rail that confirms you hit the apex—not something you climb to force the nose in.
Commit to the exit: straighten the wheel earlier than you think Kerb use that looks aggressive often costs time because it delays throttle.
- If the kerb strike forces you to hold steering lock longer, you’ll lose exit speed and overheat the rears.
- A slightly earlier apex with a cleaner exit often beats a deeper kerb hop.
Verify with a simple test In a practice session, run 5 laps:
- 2 laps avoiding the inside kerb entirely.
- 3 laps using it “politely” (just the inside tire brushing it).
If “polite” kerb use isn’t faster and more consistent, that kerb is probably not worth it for your current pace/conditions.

Mustang-Specific Notes That Change the Outcome

These are the GT4 Mustang traits that make kerb technique different than, say, a Cayman or an M4.

The car rewards a settled platform The Mustang GT4 is happiest when you keep the chassis calm. Kerbs amplify sloppy inputs, so smooth steering and pedal transitions are worth more here than “perfect” line theory.
Kerbs + trail braking often equals front push Because you’ve loaded the front tires under braking, hitting a kerb can:
- Momentarily reduce contact patch (a tiny “skip”)
- Trigger ABS intervention earlier than you expect
  Result: you miss apex and scrub speed.
Fix: finish most of the heavy braking before the kerb zone, then release the brake earlier and let the car roll.
Throttle-on balance: be patient, then decisive The Mustang tends to feel stable mid-corner, then punishes you on exit if you rush throttle. If you’re on an exit kerb:
- Use progressive throttle (squeeze, don’t stab).
- Let TC do less work—TC intervention is often “hidden” time loss.
Rear tire life is tied to kerb discipline Every kerb-induced wheelspin event is a double hit:
- You lose exit speed now.
- You lose grip for the next 10–20 minutes of the run.
Fixed vs open setup changes your kerb tolerance
- In fixed, accept that some kerbs just aren’t usable.
- In open, you can tune to reduce the punishment (see quick setup notes below), but don’t tune the car into a sofa—too soft can cause more roll and worse response.
Comparing Mustangs: FR500S vs GT4 vs GT3
- FR500S beginner tips: it’s lighter and more “old-school.” Kerbs can still upset it, but speeds are lower; your bigger problem is usually overdriving and sliding tires.
- Mustang GT4: mechanical grip focus; kerbs must be managed because the car’s mass and tire wear make mistakes expensive.
- iRacing Mustang GT3 / Dark Horse: more aero and electronics (TC/ABS behavior differs). Aero cars often dislike big kerb strikes because you disrupt platform and aero balance—but they can sometimes take flat kerbs better at speed if the platform stays stable.
- BoP (Balance of Performance): iRacing/series adjustments used to keep cars competitive. It can change how “edgy” a car feels over a season, so always re-check kerb comfort after updates.

Common Mistakes (and How to Fix Them)

Mistake 1: “I attack kerbs while still hard on the brakes”

Symptoms: ABS chatters, the car won’t rotate, you miss the apex and run wide.
Why it happens: braking + kerb bounce = inconsistent front grip.
Fix: Move braking earlier by 3–10 meters and focus on brake release. A clean release is often worth more time than braking later.

Mistake 2: “I use inside kerb to make the car turn”

Symptoms: random snap oversteer or a big push mid-corner.
Why it happens: the kerb changes ride height and load quickly; rotation becomes unpredictable.
Fix: Get your rotation before the kerb using a small amount of trail brake on smooth asphalt, then roll over the kerb with minimal additional input.

Mistake 3: “I’m fast for 2 laps, then the Mustang gets loose everywhere”

Symptoms: rear starts stepping out on exits; you’re catching slides all race.
Why it happens: kerb strikes + wheelspin overheat and wear rear tires.
Fix: Choose “boring” exits. Prioritize zero wheelspin for 5 laps and watch the long-run pace improve.

Mistake 4: “I take too much kerb in quick direction changes”

Symptoms: the car oscillates, feels like it’s on a spring, you get 1x off-tracks.
Why it happens: big weight transfer side-to-side; Mustang inertia magnifies it.
Fix: In esses/chicanes, reduce kerb height exposure: brush the first kerb lightly so you’re stable for the second.

Mistake 5: “I’m copying GT3 kerb lines in the GT4”

Symptoms: looks right on replay, feels awful on throttle.
Why it happens: GT3 aero/TC/ABS behavior and speed change which kerbs are usable.
Fix: Rebuild the line from scratch in GT4: if the kerb costs traction, it’s not the same corner anymore.

Practical Tips to Improve Faster

A 15-minute practice plan (works on any track)

5 minutes: kerb recon
- Drive 3–4 laps at 8/10ths.
- Deliberately test one kerb per corner: brush it, don’t launch it.
5 minutes: “stability laps”
- Pick your worst corner.
- Goal: same throttle pickup point every lap, even if you’re slower.
5 minutes: “exit speed only”
- Ignore entry heroics.
- Measure success by how early you can go full throttle without TC fireworks.

One-skill focus drill: “Kerb With Neutral Pedals”

For 10 reps in one corner:

Brake in a straight line.
Release brake so that when you touch the inside kerb you’re at 0–5% throttle (maintenance) and no brake.
If the car still gets upset, the kerb is too tall or your steering input is too sharp.

What to watch in telemetry/replay (simple, high value)

Steering trace: big spikes right on kerb contact = you’re trying to save it mid-bounce.
Throttle trace: saw-tooth throttle after kerb = TC intervention / wheelspin.
Line consistency: your “best lap” that you can’t repeat is usually kerb luck, not pace.

(Visual suggestions: pedal trace screenshot showing brake release before kerb; overhead line diagram highlighting “polite kerb” vs “attack kerb”; replay comparison of wheel angle at kerb strike.)

Equipment / Settings Notes (Only the Stuff That Matters Here)

Force Feedback (FFB): If your FFB is clipping (constant max force), kerb hits feel like random violence and you’ll overreact. Reduce strength until you can feel the initial kerb contact without it slamming to 100%.
Brake pedal: A load cell helps, but you can still do this with potentiometer pedals—your focus is smooth release more than max pressure accuracy.
In-car aids: GT4 ABS/TC are part of the car. Use them, but don’t lean on them—if ABS/TC is constantly working, you’re usually losing time and cooking tires.

FAQs

Should you take kerbs aggressively in the Mustang GT4?

Only the flat, low kerbs—and only when the car is settled. Aggressive kerb strikes tend to cost more in traction and tire wear than they gain in distance.

Why does my Mustang GT4 understeer more after I hit the apex kerb?

You’re likely hitting the kerb while still loading the front (braking or turning sharply). The front tires momentarily lose consistent contact, so the car “skates” wide. Release brake earlier and soften the steering input at kerb contact.

How do I know if a kerb is “worth it” in iRacing?

If you can use it for 5 laps in a row with no off-tracks, no corrective steering, and no extra TC/ABS noise, it’s probably worth it. If it only works on your best lap, it’s a trap for races.

Does multiclass traffic (IMSA / endurance) change kerb use?

Yes. In traffic, prioritize predictability and exit stability. A kerb that’s fine in clean air can become a spin risk when you’re offline, on dirty tires, or adjusting your line to let a faster class through.

Any quick Mustang GT4 setup changes that help kerb riding?

If you’re in open setup, the usual direction is: slightly more compliance (so it doesn’t bounce) without making it lazy. Common levers are damping and ride height, but exact clicks depend heavily on track and build—start with driving technique first, then tune only if you’re consistently hitting the same kerb and still getting launched.

Conclusion: The Kerb Goal Is Stability, Not Bravery

In the Mustang GT4, fast kerb use is mostly about timing and platform control: do your braking and rotation on smooth asphalt, then brush the kerb with neutral inputs and get back to a clean exit. If a kerb forces a correction, it’s not a “free” line—it’s a tax you’re paying in lap time and rear tire life.

Next step: Pick one corner at your current track and run the “Kerb With Neutral Pedals” drill for 10 reps. When you can do it without steering corrections, add throttle earlier by 2–3% each lap until you find the limit—then back it off one notch for race consistency.