Damage & Wear¶
Ten components wear as you run the engine — slowly from use, quickly from abuse. Knowing what hurts what is how you tune hard without breaking it.
What it is¶
Ten components wear: the block, head, crankshaft, pistons, intake, exhaust, radiator, gearbox, clutch and starter. Each has a health from 0 to 1, and its effect grows as health falls:
| Health | Effect |
|---|---|
| Above 0.8 | None |
| 0.8 – 0.6 | Small |
| 0.6 – 0.4 | Noticeable |
| 0.4 – 0.2 | Significant |
| Below 0.2 | Unstable |
| 0 | Failure |
Wear has two sources:
- Fatigue — slow, from running. It scales with piston speed² × load, and cold oil makes it up to 5× worse.
- Stress peaks — fast, from abuse. In a session, most damage comes from abuse.
Why it matters¶
What hurts what:
| Cause | Damages |
|---|---|
| Detonation (see Knock) | Pistons most; also block and head |
| Overheating — sustained coolant above about 110 °C stresses the block; above about 125 °C the radiator; above about 130 °C the head | Block, radiator, head |
| Over-revving beyond the mechanical limit (see Rev Limiter) | Crank and pistons; the head (valve float) |
| Low oil, or oil above 150 °C | Crank bearings |
| Very lean running, or exhaust gas above about 800 °C | Exhaust |
| Money-shifts, and torque above the gearbox rating | Gearbox |
| Clutch slip heat | Clutch |
| Cranking with low voltage, too many cranks, engaging the starter while running | Starter |
| Cold-start heat cycles | Intake and head gaskets |
Cascades. Failures spread: failing pistons hurt the crank, block and head; the crank hurts the block; the head hurts the radiator (coolant); the block hurts the crank and head; the gearbox and clutch hurt each other.
Named faults show up as symptoms: head-gasket leak, ring blow-by, bearing wear, rod knock, intake leak (unmetered air — lean and a hunting idle), exhaust leak, clutch overheat, low coolant or oil level, and random misfires. Low coolant and oil feed back into temperature and friction, which can become a spiral. Two end states:
- Limp mode — the engine is capped at 3000 RPM and the throttle is clamped to 50 %.
- Seized — the engine locks. The state window shows
SEIZEDand the engine is silent.
Visuals. The part stays visible, but smoke, steam, sparks and drips appear; scorch marks and oil or coolant residue paint onto the engine; and the exhaust shows soot, oil vapour, steam or unburnt fuel according to what's wrong. The damage silhouette in the left column mirrors health.
How to tune it¶
Let the knock control and the rev limiter protect you — but remember the damage model reads the real knock, so a mis-set sensitivity doesn't save the pistons. Watch the warning lights and the temperatures.
OPTIONS → GAMEPLAY → ENGINE WEAR RATE sets how fast parts wear: OFF, 1×, 10× or 100×.
Rule of thumb
Turn wear OFF while you're learning, and use SET WORKING TEMP to skip the warm-up. Turn wear back
on when you want consequences.
Watch out
Knock control is a safety net, not a shield. The ECU's retard is based on the sensor's reading; the damage is calculated from the real knock.
In the game¶
Reset. On the RESET page:
RESET DAMAGE— all parts back to full health; the engine keeps running.RESET TEMPERATURES— back to ambient; the engine keeps running.RESTART SESSION— reloads the scene; progress is lost.
A part swap or a full-build tune load also resets wear and temperatures.