certainly disagree with installing the pistons and dry. Engine breakin, after 35 years of engine building experience, is simple and short, but it is also a continuous process for the life of the car. I have posted what I do several times and it makes for a tight engine that burns no oil.
1. Always bring engine to FULL operating temperature before high revs.
2. Drive the car easy for the first 10 miles or so, varying the rpm's from 2,000 - 5,000.
3. Then, start bringing the engine up to maximum rpm's and letting the engine bring the revs back down by coasting in gear.
4. Repeat several times in order to create maximum heat in the cylinders.
5. Drive around at lower RPM's for several more miles, remembering to vary the speed of the engine every couple of miles.
6. Repeat number 3, 4 and 5.
7. Park car and let the engine cool down overnight.
8. Repeat all the above 2 more times.
Your engine is now fully broken in correctly and can be driven hard from here on.
Periodically, hard engine braking is necessary to get the cylinders as hot as possible and forcing the rings against the walls for maintaining proper wall smothness.
Every builder has their own specific method of breakin, and you can go back and forth forever in this debate, but it is not a complicated topic. Porsche suggests that the engines need to make about 6 million revolutions before it is broken in, and I maintain that after only a hundred thousand or less revolutions, what is going to break or break in, has already done so.
