stevenb

I've heard both stories...one being beat the hell outta it, or take it easy on it. How do you all feel is a necessary and safe (for the engine) to break it in?

5678TA

well, since no one answered.. the way I break my motor in is:

i have a pair of huge fans that i set to blow on the motor and one at the radiator.. if the temp goes too high, i squirt some water on the radiator

in the driveway, fire it up
set timing with light quickly
hold at 2k for 15 minutes, making SURE the temp doesnt go above 200
then i go 15 minutes off

repeat the 15 on/15 off till you have a total of 1 hour run time.. so basically 2 hours later i'd be done.. but i still take it easy for about a hundred miles just to make sure.. oh, dont forget to change your oil and filter after the 1 hour in the driveway.. i also change the oil and filter after another 500 miles..

Viprklr

iTrader: (5)

Your way sounds like you have a flat tappet cam.
Not necessary for rollers.

Once my timing is set and i'm happy with the valve lash I take off. I do a couple of 50% acceration runs to 60 and coast down to 20. After a couple of those I do some with 75% throttle and coast down.
Then I get back up to 60 and start coasting but DOWNSHIFTING to get more negative pressures on the rings while coasting down.
Once that's done i'll just take it somewhat easy on the engine for the first 50 miles. After that......I drive like normal whether that means a quick race, launch, or just cruising.
I change my oil 3 times by 50 miles. Again depending on oil condition somewhere between 50 and 500 miles.

ThraxXx

I was reading in GMHTTP that the proper way to break in a new motor is to run conventional motor oil and to drive at variable speeds. City driving is the best as its alot of stop and go and it gives the components time to mate. They said after the first 100 to 200 miles to drop the oil and not to be surprised to find metal flake in the oil as this will happen. They then said to put conventional oil back in and drive it again for 500-1000 more miles and drop the oil and repeat 1 to 2 more times. After about 2500-3000 miles the engine should be broken in and you can run synthetic at this point. Also, by city driving they don't mean street racing. They mentioned to avoid dropping a heavy load on it at a dead stop so no spinning the tires .

Hopefully this helps.