New engine break-in method?

[WilliamW]

I've personally used motomans hard break in on a 1986 Supra (non-turbo) and running it to 100% in 4th gear is cool and intense as hell.

I'm wondering about the window of opportunity that the break in procedure will work. Under 20 miles or so but I'd imagine that sooner is best.

What about this. I'm building an engine with Golden Eagle sleeves and low compression pistons. I have no starting map until I get to the tuner. I want to use the Motoman hard break in procedure but I don't know if the tuner will have enough time to get a map loaded up fast enough / made up fast enough to run it hard in the higher gears.

Has anyone had a problem with that or should I just relax and leave it up to the tuner to break in the engine?

[Tippey764]

if you take it easy the rings never fully seat properly and you just end up glazing the cylinder walls. The point of driving it hard is to force the rings outward on compression as well as high vacuum. that doesnt occur if you just take it easy and the rings just ride on the hone job until they glaze over netting compression losses and other issues. Talk to the people that build real motors... They all drive the shit out of them to break them in, and their motors are the ones that last the longest.

I doubt the person who bought any of our accords in 1990-1993 ran the engine hard for a break in. And most of our engines have lasted quite awhile.

[almostJDM]

high gear, high loads.

NOO cruising. either strong on the gas, or not on the gas at all. keep it in conservative rpms at all times (<4k-5k). change oil after first full ride, then 500 miles after that, then 1000 after THAT, and good to go from there

This is how I did my break in after rebuild except I went up to the vtec cross over point which is 5500 Well I went just below that and changed oil after first drive 500, 1000 then 3000, I'm going on 2 years right now

[turbo90accord]

What about this. I'm building an engine with Golden Eagle sleeves and low compression pistons. I have no starting map until I get to the tuner.

Has anyone had a problem with that or should I just relax and leave it up to the tuner to break in the engine?

your best bet would be to have your tuner break it in on the dyno. he probably has a comparable "dirty" map that he can break it in on.

[mayberry]

I just got my engine running. I drove it around for about 20 miles speeding up, staying under 10psi of boost and letting the engine slow itself down by letting off the gas and letting the car decel from around 5k rpms. That's the only way to get the rings to seat properly.

[wed3k]

I personally dont use stones, reason being that stones can glide over grooves or valleys in cylinder walls. I use a ball hone which allows for the balls to flex into those valleys. Most pro-mod and top fuel guys use ball hones for this same reason.

what valleys? there shouldnt be any valleys, just cross hatch finishes. the finish will be so smooth you wont be able to feel any "valley".