- Aug 3, 2021
- Reaction score
- SF Bay Area
- Current Rides
- 2003 S2000, 2003 Tacoma, 2008 E90 M3, 2016 STI
Hi,Thank you for the detailed write-up. How does your break-in process differ from what’s in the manual? By no means am I being sarcastic; I really want to get this right before mine is delivered (est end of Jan). Thanks again!
Others will likely have other details to add, but I believe the single, most significant detail left out of the manual (and all break-in manuals to be honest) is this idea of gradual acceleration/deceleration followed by a cool down period. Other details to be mindful of:
1-When starting up from cold, it's important to allow the engine/oil to warm up for a good 5 minutes minimum before putting your foot into it.
2-Regarding the mileage intervals/speed limits, I'm not sure how critical these are, but honor them at your own discretion. Some will swear that the ring seal must be performed in the first 100 miles, so don't drive it too lightly. In other words, give it a handful of light pulls with plenty of cool down time in between them on that first trip home from the dealer. With a brand new vehicle, those MPH limits are probably there to give the driveline a chance to break in without overheating. With that said, brief, gentle pulls shouldn't hurt anything as long as your sustained speeds are aligned with the manual.
3-Keep the transmission in manual mode in order to slowly accelerate/decelerate using the engine. This is your biggest insurance policy against "catastrophic engine damage" aka cylinder head overheating.
4-I believe it's important to avoid loading up the engine at low RPM's. So, to avoid this, downshift into a lower gear when initiating a pull. Engine loads at low RPM's place more stress on the internal components as compared to higher RPM's. At low RPM's, the power stroke is spread over a longer period of time. Higher RPM loads, by contrast, have quicker power strokes, which is better for the main and con rod bearings. So, when on the highway, simply downshift from 6th into 5th or even 4th to place the RPM's somewhere around 3K. This 392 has no trouble pulling nicely from 3K, so I have been using this as my minimum RPM when initiating my pulls.
The manual seems fairly reasonable about the time it takes to break-in the motor. 5-While I describe this process as "hard", its by no means irresponsible or negligent. Rather, it's highly controlled and scientifically based. Some would argue it's necessary in order to avoid a leaky, underpowered motor that will ultimately have a shorter lifespan. By 500 miles, it should be fully broken-in, especially if you practice this accelerate/decelerate/cool down procedure.
6-Good articles on this topic are abundant, but here are a couple that spell things out. I especially like the second one as it's very detailed. Engine builders seem to honor these guidelines from what I have found.
Dispelling Engine Break-In Myths With High Performance Academy
Engine break-in is one of the most widely misunderstood processes in the automotive world. High Performance Academy seeks to change that.
Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power
New Engine Break In Procedure For Cars, Motorcycles, Motocross, Snowmobiles and Boats