this link was provided by member, 2fixA, on another thread. it deserves its own.

"What's the Best Way to Break in
a New Engine ?? The Short Answer: Run it Hard !" -mototune

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

does anyone kno this to be true? does it sound feasible?

 

that's funny, did you just get that from the post I put up a few minutes ago?? I know the guy who drove my car from the docks to the dealer, and knowing him I can bet it was well broken in... just noticed you did respond to my original post...

it's just such a contreversal subject, hard to pin people down on it..

 

ooh~

 

To properly break in an engin you should not accelerate hard for the first 2,000 miles. Almost no one does that but thats what you should do because it moves all the oils around and everything gets nice and lubricated so after the 2,000 miles you are able to push the motor harder than you would if you didnt do that.

 

2000 ? I've always heard 1000 miles :?

 

I've heard 2k, but I dont see why 1 wouldn't do the trick...as long as your not driving hard in a car that only has 3 miles on it. Since I've heard 2 and you heard 1, lets say 1,500 miles. :D

 

never heard of this SECRET...anybody verify this?

 

I know the MotoMan- from Mototune

He actually built my Yamaha R6 motor for road racing-
he's gooood.

loose sum up of his break in theory:

a new engines rings get ground into the cylinder walls and seat.
the rings themselves exert 5-10 psi of force against the cylinder.
However during combustion there are 3000psi+ of force created. How do you
think some of that energy doesn't escape past those rings? when the rings "seat"
they make microscopic grooves in the cylinder walls. these tiny "tracks" that the piston/rings glide in help keep the combustion pressure from "leaking" past.

When u rev up an engine in gear (on a dyno) and then let it engine brake down- it creates vacuum as the rpms go back down. the vacuum actually forces the rings
into the cylinder walls harder thus creating a better seat or pressure seal.

When MotoMan breaks in fresh engines, he puts the bike on the dyno and puts it in 1st gear and revs it up to the limiter, cuts the throttle and lets it come all the way down.

He does this 4-5 times


When i got my Scion xB i did this in the dealership lot. The salespeople ____.
Doing this also helps you weed out a lemon motor early- while it's under warranty

eej

 

oh the MotoMan runs Mototune USA the website mentioned by HneFrdo

 

Sounds like someone may be more concerned with "performance" then with having a long lasting dependable car.

Always break in your car by driving slow and easy for the first 1000 miles!!!

 

I have used this technique on four of my Fiat engines and have had very good luck even with hi-compression / hi-rev. engine.

 

i dont know about the whole break in process thing....

think about it.... like when a shop or person builds a true race car, where and how can they break in a newly built motor??

back in the day when i was in the racing scene.... we'd build a motor from scratch and drop it in the car.

since the car was a track only car (not suitable for streets and not meeting dot standards).... you really couldnt break it in (without getting tickets on the street)...

i mean, yeah, we took it up and down the street by the shop a few times.... but not 1000 miles worth.

we'd just build a motor, drop it, tune it, then take it to the tracks and run it hard....

HOWEVER

i am taking it slow with my motor.... why?? hmmmm..... maybe because im worried of the possibility of something breaking...... i dunno really....

and if you say that you can gun a newly built race motor because its built to handle it, perhaps you shouldnt gun the 1.5L your xB came with because it wasnt built to handle it.

 

some friends told me drive it hard, some friends told drive it slow, which way is better?but they all told me change the oil around 500 miles. . and how about the tranny, I have a auto box, what should i do to the tranny, need to change oil around 500 also?

 

Well this is a new one to me! I have never heard of this break in procedure! I'm a mechanic and to be honest It's not realy about running the car fast or hard ! It's At least as I was taught more about RPM Dont keep the RPM the same i.e. dont run the car at 70 for two hours straight. Adjust the cars spped to adj the RPM and the most critical is the first 200 miles with full break in at around 2000. Oh yes its importan to not rap the RPM way up in the inital 200 miles! Just drive your car normaly your not spped racer! Im not saying this guys method is BS I just saying I have never heard of it! Every mechanic has their method of repairing something one mechanics method might work for one but not another! So my advice the same way as another pice of advice!

 

OK, let's say this guys theory is true. How much extra power are we possibly gonna get out our little 1.5's? He's talkin RACE bikes. Not daily drivin, boxes on wheels. Those BIKES have more power out of the box than our cars do. And they race, so of course every ounce of power is gonna help. Our boxes will never see a racetrack or dragstrip for the most part. I don't know about you, but an extra 1/2 a horse isn't gonna help me do jack ____!!!

 

I'm just saying screw it and driving the hell out of my XB...Two reasons...One, it's a lease...And two, it's engine is under warranty...

 

Here is a link from overboost.com. I found it by googling this: new car engine break in procedure.
http://www.overboost.com/story.asp?id=1250
It's mainly about replacement engines; brand new, rebuilt, used. But there is a lil bit on new vehicles

 

Taking into consideration from both sources ( the Motoman and Overboost ) i did a similar break in on my auto tranny RS1. From the dealership it had 2 miles on it. As soon as i got in and drove it, i kept it in 2nd gear all the way back home ( 8 miles additional ). When i got home, i installed all my parts including an intake and got the xB raod ready. When i was done that night, i took the truck out and kept it in 2nd gear for another 20 miles. I would bring it up to about 50-60 MPH and then let the engine bring itself back down. This caused higher compression ( i think its called higher, this is when the piston rings are forced out and forced to seat ) and then brought the car home. The next day i used the car for work, and the day after that and so on. I changed the dino oil out at 200 miles, adding more dino oil. At 1200 miles i changed the oil again, adding Mobil 1 synthetic.

I have seen on these boards where people with very little mileage on their cars have noise from the engines. I can tell you that in my case, there is not on rattle or any other noise from under the hood. My intake makes more noise then my engine, and im at 3500 miles now, and getting about 33 MPG as well. Did it make a difference? I really dont know. I can tell you that the last car i bought ( my Neon ) i didnt do this kind of break in, and instead did what the manual suggested. Ever since about 2K miles, the car taps like Sammy Davis Jr. and it just keeps getting worse with age.

 

Also for engines that are installed in a Toyota from the factory, they are all run for a period of several hours to break them in before installation in the vehicle. They found that that eliminated 99.9% of all new vehicle engine failures. I'd expect that this is a common practice for most major car makers. Not all, but most

Mike

 

Proponents of the high-rev break in seem to focus on the performance/power gains which is fine, but have any of those engines been seen after they have 100-150k miles on them? Obviously not a Scion yet, but my understanding was that a gentle, varying rpm break in allows an engine to do better in the long run, and last much longer after the first 100k.