At the very least I'm going to have all new bearings and rings when my rebuild is complete. Some say that the same as breaking in a brand new engine, some say it is not. Some say that the usual MINI recommended break-in procedure of keeping the revs low along with varied rev points when driving for the first few 1000 miles is the way to go. There are also many that say to drive it like you stole right off the bat is the way to go. Reading lots of posts and articles all over the net there are more opinions on how to break-in a rebuild than there are people with ass.... I've not formulated a plan nor have I discussed this matter with the engine builder, Chad of Detroit Tuned, as of yet. I thought I'd start some discussion on what people think is the way to go.
I'm in the get it to temp and run it hard group. I did that on my r56 (different I know) and I still get people asking me if I am running a tune. It started with a motorcycle guy but it does translate well into cars. The key is getting it to good operating temp BEFORE running it hard. Here is the Article There is my A$$... Uh opinion. EDIT: I've also done with with my 2006 350Z after I got the rebuilt block and had good results as well!
I can only relate what has worked for me over the years, that is, the usual MINI recommended break-in procedure of keeping the revs low, up to 3k on cold engine then up to 4k when warm and along with varied rev points when driving for the first few 1000 miles. Then change oil @ 1,000-1500 miles. Your car is not warmed up till the oil temp is at least 200 degrees. Never hammer a cold engine, things in there have to warm up and expand so the oil film can do it's job in the smaller clearences of a warm engine. Use the gears to make the engine work, keep those rings pressed against the cylinder walls. Use the brakes not the engine to slow down.
Don't assume its warm because it blows hot air out the heater, get an oil temp. gauge if you don't have one.
I would ask the man who built your engine. Chad will know. For me I broke it in as the engineers at MINI said to. One thing I would do is dump the oil at 2,000 miles. That's just me I like to keep clean oil in my cars.
Personally, I'm a "drive it like you stole it" guy. The article Redbeard linked isn't far off my planned methodology.
I'm not sure about a car, but when we did a complete rebuild on an (reciprocating) aircraft engine, it was "throttle to the firewall" and hope for a lift off. Jim
I also followed MINI's recommendation for engine break-in...drove it pretty carefully for the first 1200 miles. Changed the oil at 1800 miles and have driven like I stole it ever since. I also change the oil every 5-7,500 miles.
I'm kinda in the middle, I do some of each.....generally I don't drive it too hard, but I do use the revs and when I do I keep a good load on it. You can't drive it hard very long anyway as traffic and speed laws will intervene.... I do advocate an early oil change too, around 1000 - 2000 miles at most. I wouldn't do a track day till I had 1,000 or more on it and an oil change, but other than that - I'd use what god (or Chad in this case ) and MINI gave me. All I can say is none of the cars I've driven from new this way have ever used any oil - I take that as a good sign - the most miles I ever did this way was on a Porsche 914 2.0L at over 150K.
One of the things I'm going to sorta be up against here is once I get the back its 223 miles from Detroit Tuned to my door. The vast majority is highway too. Then soon after it's off to the Dragon, that, 422 miles door to door. All but the last 55 are highway. There is no daily commute and I'm going to have make sure the short trips I usually do turn into longer ones. Like a lap around Columbus to go 2 miles down the street to the post office. I figure it'll be right around 1000 miles on it when I get to the Dragon. Going to be interesting...
After pickup, vary the speeds, vary the load on that first 233. After a very good warm up, run it fast but not hard for the next couple of hundred. Enjoy the run down to the Dragon, first thing at the Dragon change your oil and filter. Then let runs on the Dragon be the real break in cycle. It should be fun and give you a solid engine. Just a thought. Don
:cornut: Me? I'm with Crashton; do what Chad at DT says especially as he is providing the limited warranty. Jason
Nathan, look at going east on St Rt 2 at Toledo and then taking 95 down to Waldo. Get a bologna sandwich at the G&R Grille and then motor into Columbus. A much better route with 2 lane roads.
Vary engine speeds and dump the oil at 500 miles that's what we've always done with the TR engines we've rebuilt.
Nate, I drove mine home after my rings & rod bearings, don't sweat it, just do like everyone says, up-n-down with your pedal, (I pissed a few people off but I don't think I kept a constant speed or rpm the whole way) the not over 4500 thing is good till after the first oil change (1500 to 2000), but don't be afraid to open it up to get to that 4500 (esp in the lower, less torque stress gears) after a couple if hundred miles or so.
I worked for Quicksilver Race Engines. Quicksilver has been in the race engine business since the 60s. They specialize in SCCA engines, especially Ford based engines. They are and have been one of the best Formula Ford engine builders in the US. The 1600 CC Kent based engine is used in Formula Ford, and they build engines that make 110 to 112 horsepower. They do not ship engines that can’t make 110, and 112 is a killer. The point is not how much power these engines make. To break the engines in they put them on a dynamometer and pay attention until the temperatures come up. Monitor the oil pressure very the throttle a little but mainly don’t let them idle below 1500. Then they walk away and in 15 or 20 minutes the sound changes. (The engine seals up) Then they hammer it on the dyno. If the engine wasn’t broken in the power would not be that consistent. These engines have very round cylinder walls. They are honed with deck plates and hot water circulating through them, but modern engines should seal very quickly. Quicksilver also created the kit to turn the Honda Fit engine into a Formula F engine. They have also done an extensive amount of dyno time with the engine. Brand new Honda Fit engines that are only dry run to insure oil pressure from the factory seal up instantly.
Nate, I see that Jan is helping out a bit in the rebuilding. You might want to ask him, if you haven't already done so, about his recommended break-in procedure.
Nathan, My car passed 600 miles on the way to its first AutoX and I have been pounding the crap out of it ever since. Starting in '08 I've upped the abuse to 13 or 14 track weekends a year. Car will pass 95K at the end of this month on the drive to Cresson. The engine gets maintenance when necessary. This past weekend it got new plugs when it started throwing missfire cylinder 4 codes at TWS. All the internals are OEM original. I am MINI testament to "let things seat then drive it like your gonna use it". Alan