L&M Newsletter

Our Engine Break-In Procedure

We use a break-in procedure that goes against the outdated information that can be found around the internet and various social forums. Due to the smooth cylinder finish in today's engines we run the engine immediately to seat the rings (grind the ring) to the cylinder bore before the cylinder surface finish becomes a mirror. We have limited time to do this before the roughness disappears.

Imagine a piece of sandpaper that gets dull and if you keep sanding it doesn't cut but just gets hot, well the sandpaper is the honed cylinder finish and the ring functions as the piece of wood.

Preparing The Engine To Run For The First Time

1. Prior to starting all fluids must be topped off and the car ready to run. Double check all wiring and make sure all cooling equipment is functional.

2. The coolant system must be purged of air before starting. We use a vacuum coolant re-filler and find it works best. The inter-cooler system must also be purged and inspected for proper circulation.

3. The engine must be setup to start immediately without a lot of false starts and excessive cranking. If the engine is not firing up in a reasonable amount of time double check the entire system; fuel pumps, injectors, spark, the tune, etc.

Starting The Car

Start the car, DO NOT crank the engine to prime the oil pump, the engine will have instant oil pressure on start, let the car run to cycle the thermostat & fans, check for leaks at this time as well. When warming up to cycle the thermostat, observe the top and bottom hose temperatures, if both hoses are cool/warm and the temperature gauge is rising or you expect the temperature gauge to rise and it's not, the there is a cooling system malfunction and MUST be fixed immediately before continuing. The hose temperature differential on a warmed engine is general around 50-75 degrees.

Avoid excessive idle or very low load operation.

Do not conduct deceleration operations at this time. Deceleration operation is an extremely low load condition that reduces ring pressure to the cylinder to near zero, polishing the cylinder and removing the roughness. Low speed and baby throttle operation just polishes the rings, we need combustion pressure to push the ring against the cylinder wall and seat in the ring which is accomplished by medium to high load.

The one common thing from 1950 to 2016 is to not overheat the ring. Take your time between dyno pulls to allow the ring to cool. This would be a good time to review your data logs and tune.

After verifying thermostat cycling and full leak check, get it strapped down on the dyno and start making WOT pulls. Keep the first one low in the RPM around 5000-5500 then work your way up from there. After a couple pulls the engine break in will be about 60-75% complete. Finish your tuning sessions and then go race.