COMP CAMS 274H Camshaft Break-In Procedure

Just for fun, here are the many points of attention to observe during the break-in of the new camshaft in the Cobra ERA’s 427 Side Oiler. Improper break-in could later compromise the qualities and performance of the Ford FE V8.

Preparation before camshaft break-in start-up

Oil change with a new filter (pre-fill the filter with oil before installation).
Fill the oil pan with 7 liters of Valvoline VR1 20W50.
Add 100 ml of Rislone ZDDP (≈ 1/3 of a bottle).
Coat each cam lobe and lifter with MoS₂- or zinc-based assembly lube (never assemble dry).
Check ignition timing: the engine must start immediately (no extended cranking).
Place a fan or forced airflow in front of the radiator — temperature rises quickly at 2,500 rpm.

Start-up and Break-in

Start the engine → immediately stabilize between 2,000 and 2,500 rpm.
- No prolonged idle! (risk of cam lobe scuffing).
- Slightly vary engine speed (2,000 ↔ 2,500 rpm).
Let the engine run for 20–25 minutes → monitor coolant temperature, oil pressure, and any potential leaks.

Basic Settings (if switching to K33-248-4)

Cam timing: target an ICL = 106° (typical XE274H) to maximize torque from 3,000 to 5,500 rpm.
Ignition timing: 34–36° total, fully in by 3,000 rpm.
Valve springs: use the springs supplied in the kit and verify installed height / coil bind clearance.
Break-in: ZDDP additive, 2,500–3,000 rpm for ~20 minutes, then perform an oil change.

Bonus Adjustments (major impact on ET)

Tire pressure optimized for grip, clean first-gear launch (no sudden full throttle).
Total ignition timing: 34–36°, fully in by 3,000 rpm.
WOT AFR: ~12.8–13.0.
Rev limiter:
- XE274H ~6,000 rpm
- F-238 ~6,200 rpm

After Break-in

Allow the engine to cool down → recheck valve lash / hydraulic lifter preload.
Drive up to 100 km maximum (gently, no over-revving and no prolonged idling), then:

Perform an oil change with a new filter.
Switch back to Valvoline VR1 only (no additive, unless for track use).