Created with Sketch. Created with Sketch.

Engine Break In Procedure

Thanks for purchasing a Sneed4Speed engine!  The first part of an engine’s life is the most important time.  This sheet will walk you through first fire up and break in.


First fire up -


Fill engine with 5-30w non synthetic motor oil.  


Prime the oiling system by removing the spark plugs and spinning the engine over with the starter until oil can be seen in the valve train area and in the oil filter.  Do this in burst as to not wear out the starter. Once oil is up, check for leaks, if no leaks move to step 2.


Make sure cooling system is full with no leaks.  Open vent at thermostat housing to insure the cooling system is full.


Reinstall spark plugs and start engine.  Engine should fire and fast idle. Check for oil leaks and pressure.  If good, allow engine to fast idle until it warms up.


Once engine is warmed, you can start break in.  This can be done on a dyno or the road.


Start in 3rd gear at 2500rpm and apply gradual throttle to full throttle to 3500rpm.  Lift and let engine slow the car. Repeat 2500-4500, 2500-5500, 2500-6500, 2500-7500 (or redline)  Always check AFR gauge, listen and look for unusual noises. If you have one or the AFR gauge reads to lean STOP IMMEDIATELY until it is repaired and then restart break in.  Once break in is complete drive car at normal speed for 5 mins to cool engine.  Then return to garage and let engine fully cool and check for leaks. If no leaks, you can drive car normally now and change oil in 500 miles.  After 500 mile oil change use normal oil change interval not to exceed 5000 miles between changes. After 500 miles you can use synthetic oil of your choice in weights 5w-40 or 5w-30.