Engine Break-in

Before you set a new track record… think about that brand new engine. Be kind to it, and it will be kind to you and your wallet!

The engine should be given three break-in sessions of approximately 15-20 minutes:

1. Keeping RPM below 7,500 and moderate throttle.
   1. You should use this opportunity to also bed your brakes.
2. Keeping RPM below 10,500 and full throttle.
3. First half session (~10min) below 10,500rpm, then allowing full rev out all the way to the limiter.

The engine should be allowed to cool after each session.

This also gives you a chance to get broken into the car. Fluids should be checked after each session, and you must torque-check the wheels before every session!

Following these three sessions, you are good to go. The car is very balanced but will bite back if you horse it around. Find your limits slowly and work into the car. It likes to be balanced in the corners: deep trail braking and yanking your foot off the brake at mid corner, will not give you the results you want. Apply brake pressure quickly, but roll it off smoothly.

Learning to use the shift lights will take some time too. Most people are tuned into changing gear by 7,000 rpm. If you short-shift, you are not even in the powerband.

Wheel horsepower from a customer-owned Rush SR.

The same chart, on its own page: Dyno Sheet.

Change the oil when break-in is done

New cars ship with a break-in oil rather than the service oil, and running the three sessions above is what it is there for.

Change the engine oil and filter when break-in is complete. Break-in is when the engine sheds the most material, and it ends up in the oil. Leaving it in is the one way to turn a careful break-in into an expensive one.

Oil and filter specs are on Fluids; the procedure is Changing Diff and Engine Oil.

Note

Break-in oil runs slightly lower oil pressure than the service oil, so the OilP RPM Ratio reads lower until you change it.

That does not move the alarm thresholds. Check Oil Pump below 80% and Low OilP below 45% still mean come in, on a new engine most of all. Note what the ratio reads across the three sessions and again after the oil change, so you know your own engine’s numbers rather than a page’s.