Breaking your new Mini in, or any new vehicle for that matter. Are you really just breaking in the engine, and not the other parts of the car as well? Like the tranny, etc.?

Also, why is this so necessary? What happens to a vehicle that isnt' broken in, and driven very hard? Is it something that always happens, or just potentially can happen, or what? And why is the magic # 1250 miles? What has happened by then to be able to use WOT, and finally be able to experience "Spirited" driving? =)

There's nothing that can be done during production of an engine to minimize the need for a break-in period?

TYIA =)

 

the clutch needs about 300 miles to wear off the first little bit. until around 300 miles it seems like the clutch is touchy, like it doesnt want to slip much.

 

Maybe, must Maybe ... MINI knows what its talking about in the Manual.

Of course, its your money, your car

 

A clothes hanger usually works. Either that or a flat, long, piece of metal an inch wide.

 

Steeroids,

When the engine is new all the internal components are tighter than they should be and also the metal is still a bit rough (on a microscopic level). Running-in is important because it gives the components are chance to wear in slowly and efficiently and it allows all the components to seat properly. The engine also runs hotter when it's being run-in, so driving it softly prevents it from getting hotter than it should during that period. There are other componenets on cars that also need time to run-in (such as clutch, transmission, tires, brakes, etc), but the running-in period for these components are generally shorter than the engine's running-in period.

If an engine is not run-in properly it is quite possible that it won't be as efficient and it won't produce as much power as it should. It will also need more maintenance than a well run-in engine. There are some people who believe that it's actually good to drive a car hard while running in, but they are the minority.

Engine manufacturers already have done a lot to help the run-in period take less time. Older engines used to take significantly longer to fully complete the run-in period.

I hope this answers all your questions.

SuperCharged

 

I can only speak for myself so here goes:

Drive the car from day one like you intend to drive it, the car comes with a warranty if something is going to break I want it to break in the warranty period so I can have it repaired or replaced at the manufacturer's expense not at mine. With todays technology and tolerance of engineering the build process is very good compared to years ago.

"THDUKE" was driven as if it was stolen and being chased by the cops from day one, it now has 104,570+ miles and with the exception of the JCW install at 18000 miles the engine and drive train has not been touched, this year alone this car has been driven on the track for a total of 29 days for at least 3 25 minutes sessions per day.

That means that for about 20 minutes 3 times per day for 29 days of this year the car lives in 6000+ rpm range, I change oil every 5 track days, still have original every thing for engine and drive train.

So from my point of view drive it as hard as you can and break in process be damed. If it breaks let them fix it thats what the warranty is for, on the other hand use the break in process, and if you baby you car all the time it wont matter anyway.

I personally believe that you want the rings to get seated early in the engine's life at the very high rpm and high temps, if it does not break under these conditions it will last a long time.

 

I believe the 1250 and 4500 break-in rule is more for the coating on the supercharger vanes than for the rings.

Who really knows how much efficiency is lost due to the unorthodoxed approach of not following the manufacturer's carefully-researched warranty requirement?

 

If you say so, but how do you account for the break in procedure for the Cooper where there is no supercharger

 

Reminds me of touring the Ford Mustang plant in Milpitas in 1979. As the cars came off the line they'd fire the engine and within 15 seconds of the first time the car was started, paint two black streaks off the end of the assembly line into the shipping yard. Every car. I had to ask, and the answer was: "If it's gonna break, we want it to break here." A more honest answer may have been "Hey, they ain't ours and this is FUN!"

 

Are you merely assuming that the numbers, 1250 miles, 4500RPM, were the result of a well thought out/researched test, or could it be it was more of a generic figure for cars of similar engine size/cylinders/etc.

The more you baby your car, the less likely the car will break down within the warranty period, therefore making it less likely that the manufacturer, in this case Mini, would be responsible for making any needed repairs for such failures. So it makes sense that to be in Mini's favor, they would recommend you take it easy on the car for as long as possible. Though of course I realize 1250 miles is very much shy of the 48k? mile warranty mark.

Also, question for dkstone. Have you dyno'd your car multiple times with various different engine mods, and compared those figures to people that claim to have broken their car in properly? That'd give a good figure, at least horsepower wise, to judge power loss, to challenge the necessity of the longish break-in period.

Also, can we get any pro's in here to put their 2 cents in? Like Randy maybe (he always seems to repond to posts with his name in them, perhaps he searches for "Randy", this is my hope anyway, can get his attention to my question )

Hoping I can drive my Mini fairly quickly from the get go. 1250 Miles just seems like such a long time hehe. We'll see, won't get it for another month or so.

Thanks again for the replys, keep em coming if you have more to add!

 

Thats weird, I was just reading about breaking in cars today. Here is the article I looked at.

http://www.canadiandriver.com/articles/jk/030108.htm

 

I broke in my MC this way.

I drove it at or just under 4500RPMs going under and over that to vary it. I took it to close to bounce(red line) right from the get go. Not much, and never held it there.

When I got close to the end of the break-in, which took less than a week, I ran the car harder, holding 6k, not upshifting till I wanted to vary revs, and bouncing the tack on ocassion.

I now cruise 600+ miles a week on the highway, turning 3100-3400 RPMs,

My MPG is around 37, the car goes like snot, is as solid as day one, feels better really, and I have 55k miles on it

 

Many thanks for the article link, quite informative =)

 

Found this article doing a Google search. Seems interesting. You guys check it out, and hopefully someone with a decent amount of know-how let me know what you think about this guy's logic of breaking in a motor the hard way.

http://www.mototuneusa.com/break_in_secrets.htm

 

When I spoke with Randy at the Chicago pulley party, my car had about 600 miles on it. I asked Randy about his opinion of the break-in procedure. He told me (not a direct qoute) that at I shouldnt worry about breaking the car in anymore. The rings where set and everything was good to go. He also recommended an oil change (but I didnt get that done until 2600). I hope that helps.

 

That's the article I was looking for and you beat me to it. I have plenty of freinds that agree with that and do the same. And of course is the break in plan I follow too.

 

I pretty much followed the method described in the Power News Magazine article to break in my 2005 MC. I have no way to evaluate the benefit/detriment as a result. That was done a year ago and I only have 4400 miles on it at present. As of today it runs great. I don't moto-x or race but it goes fast enough that my wife won't ride across the Dragon with me anymore, but maybe that is just my driving:smile:

 

I'm about to take delivery on my Mini, and have a question for those that have followed a "hard" break-in procedure. Did you switch to petroleum motor oil for the break in, or just stick with the synthetic that was in your Mini as delivered? Also, did you do a low milage (<100 mi) oil change?

 

My guess is you'll never know the difference no matter how you break it in. To me, however, following the manufactors recommendations makes more sense than doing it the way someone who wants to be "different" tells you.

Everybody always wants to be the first to say the tried and true method of doing things isn't correct. Usually they are wrong, but, in general, people like hearing that things aren't as they had previously been told. That's why conspirancy theories are so easy to start......

 

I feel very sorry for the person who buys this car from you. I hope you will be honest egnough to give such an accurate description to any prospective buyer of your treatment of the car.

This opinion and all those who think they know more than the team of engineers who design the car baffles me.

The wear on our cars have a cumualitive factor, a second year engineering student learns about fatigue and fracture mechanics. Put simply.....all of the parts in our cars have microscopic microcracks and imperfections in crystal structure and stress concentrations. The frequncy AND magnitude of stresses placed on a component shortens its lifespan by a measureable amount. If driven hard your car will have components fail earlier and more often, they will not fail under warranty they will fail out of waranty because of course that is in part how they determine the warranty, is the lifespan of a component under abusive conditions (wear items excluded)

By not following the instructions of those who know your car best and have a vested intrest in a reputation of quality associated with thier product (whether you have an engineering degree or not) you are really setting yourself up for a fall

 

I've been trying to look into this a lot and have found some interesting stuff out. For starters, I am not a gearhead - but all three of the other people on my team at work are. One of them is the head of the local SVTOA club. He has a lightning (03ish), an svt contour(umm, 02?), a cobra(03), and an older mustang of some kind(mid 90's?) set up for racing. His dad retired as a mechanic at a Ford plant after working there his whole life. His statement to a co-worker on getting a new car was "Drive it like you will be driving it every day."

Moving on to what I found, most of it has actually had to do with airplanes! Small engine planes like Cessnas have to have their Internal Combustion engines broken in just like cars do. It's arguable that they have even more stringent requirements for break-in.

There are three main camps on break-in. the first and most popular is the "Follow the manufacterer/dealer break-in to a T." The reasoning here is generally that the dealer knows best. Occasionally someone will point out high temperature caused by parts wearing against each other as well.

The opposite (and smallest) is the "drive like you stole it" group. they generally seem to talk about being gearheads or knowing them and driving all their cars that way. They mention the advances in manufactering and how long cars they've dealt with have lasted.

The last (almost as big as the first) is a mixture of the two. It seems that this camp prefers the thought of following the manufacterers babying procedure with a twist. Put the engine under a decent load regularly to seal the piston rings.

Some of the most interesting highlights were from a company selling "box engines." Basically the engine arrives in a box and you only (lose use) need to mount it, add the bits and break it in for your car. They were the only actual engine manufacterer I could find with break-in instructions (I didn't look super-hard and am not counting car manufacterers as they usually don't make the engine). They wanted you to do a run up and engine break down the rpm range at intervals throughout the break-in period, while maintianing a gentle break-in outside of that. They also had a relatively short break-in.

The gist of what I've learned and will probably do is this. I am going to accelerate at about 50-75% pedal in one gear from around 3K to around 6K RPM and then let the engine slow itself back down about once every 50-100 miles (and the first time will be in the first 10 I drive it). This short load will not push redline and will not last long enough for overheating to be an issue. I will not do this until the car has had a chance to warm up. The rest of the time will be the directions to a "T". I think this method will allow the pressure on both sides of the piston rings that seems necessary to properly seat them (read some of the articles on airplane engine break-in, good stuff) while not allowing the heat build-up to be an issue. I am probably going to do an oil change sometime between 1500 and 2000 miles unless my gearhead buddies want to help me do it a couple more times before the regularly scheduled one. Redline appears to be something to work up to after the first 1250Mi in all but the extreme break-in camp. The best information appears to be in the aviation community.

Here's some good referance material:

Do lot’s of hard breaking in:
http://www.mototuneusa.com/break_in_secrets.htm
http://www.aircooled.net/gnrlsite/resource/articles/engnbrkn.htm

Middle of road:
http://www.enginesonly.com/break-in.html[/FONT] / http://www.enginesonly.com/newsite/break-in.html
http://www.cessna.org/benefits/articles/breakin.html (airplane)
http://www.type2.com/library/engineg/engbreak.htm
http://www.stealth316.com/2-breakin.htm
http://www.aera.org/consumer/engbrkin.pdf
http://www.lycoming.textron.com/main...neBreakIn.html (aircraft)
http://72.14.207.104/search?q=cache:...break+in&hl=en (aircraft)
http://www.ntnoa.org/enginebreakin.htm
http://www.hastingsmfg.com/Service%20Tips/breakin_procedure.htm
http://www.g1teg.org/howto/enginebreakin.html

Soft breaking in only:
http://www.jpcycles.com/Tech/Articles/enginebreak.aspx
http://www.sdpc2000.com/faq/kbhowto.asp?mt_node=3
http://www.ducati.net/faq.cfm?id=51 (Ducati – apparently ring-seal is taken care of at the factory on these)
http://www.idavette.net/hib/eng-brkn.htm
http://www.faqfarm.com/Q/How_should_you_'break-in'_a_new_car
http://www.brockracing.com/tech_breakin.htm

Other (forum discussions on the same thing for example):
http://forums.noria.com/groupee/forums/a/tpc/f/616604995/m/470100848/r/3521000801
http://forums.macrumors.com/archive/...p/t-95891.html
http://sportbikeguy.com/garage/floor/breakin.html

 

CeridianMN, a very nice survey of a "religious" topic.

 

agreed! well done. I like the non-biased approach. Maybe one of the mods could make this a sticky and we can put it to bed. Thanks!

 

regarding the rings, the best way to break them in is to run hard. they need high pressures to be seated, and they need it early in the engine's life to properly form themselves to the cylinder walls (and the cylinder walls to them). This means hard acceleration. Unfortunately, the crankshaft and piston rod journals and bearings need something a little smoother although not at constant revs. In a modern engine, the fit of these parts will be better than back when the idea of running a thousand miles gently gained popularity. It is a possibilty when they fit too tighly and need to be worn down that you can 'spin the bearing' which means that the touch metal faces would weld together and effectively turn your bearing into a grinding wheel. A lot of times in motorcycle and racing engines, the piston seal is more important so the 'burn hard' method is often applied (since poor compression can destroy power ratings and the engines are torn down every few thousand miles anyway). That said, I've been kind of curious to see the results of various break in methods after the engine has been run for a hundred thousand miles or so. The pistons would definately look better from a hard burning but I'm curious as what effects it might have on the bearing surfaces. Myself, I'll use a method that mixes hard burns with slow steps up to higher revs every few dozen miles. It seemed to work for my V8.

 

Beware of one thing regarding airplanes - 70% to 75% power as mentioned in the articles is practically flat out, throttle to the wall running, depending on altitude and temperature. This is not middle of the road, but rather close to the thrashing as recommended by mototune. Failure to do so results in a teardown and hone of the cylinders if oil consumption remains high due to the glazed cylinders.

Jim