Performance engine break-in (Piston Rings)

[Justin Farrington]

Normally on most rebuilds I would be gentle and I’d avoid WOT for at least 500 miles. However, I recently rebuilt one of my personal engines and it’s designed for high end performance, and the Hastings piston rings say to break in the rings by going WOT 35-55mph. I have consulted about 5 certified Master Technicians and I seen to get different answers from them. Some say to break it in like any typical engine, some say to drive it normally in the city, and some say to go WOT on a private road or on the highway (between exits in town). Just looking for some more opinions on what may be the best and safest route. Please note that this vehicle is street legal but also will spend some time at the track.

Topic

[college man]

see if this helps. 🙂

[Justin Farrington]

I had actually already watched that video (it’s how I ended up here asking in the first place). I just decided to go the mixed route and constantly change the RPM between 700-3200. Never staying at one set RPM for more than 5 seconds. After doing that (in neutral with the wheels off) for about 20 minutes, I revved it up to 4000 RPM real quick and dropped it immediately. Let it vary from 700-3500 for another 5-10 minutes and then shot the RPM to 4200. Then I let it idle at 750 RPM for 5 minutes then varied the RPM for another 4-6 minutes then shot the RPM to 5000 and immediately dropped it to 3500 then slowly let it drop to idle. Sounds smooth except the valves tapping the seats lightly. Thanks though.

[EricTheCarGuy]

There are a lot of different opinions on this. I think you chose well by varying the rpm as that is what will break them in the best. Keep us posted on how things work out for you.

[Author]

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