Maybe we are taking the engines to the track too early...
Guilty as charged.

As far as break-in...

I've never user the extra shim, maybe I should.
We pre heat the engines usually 200 thats as hot as I can get it with the hair dryer. I usually turn the LSN out 1/4 and foil the head and idle the first tank out at 220-230. They have had no problem idling the first tanks, I usually see raw fuel spitting out as it idles for a half hour. I place the piston BDC and let the motor cool down to 110-105. I've tried 2 approaches from this point my first motor Idled almost 10 tanks out just like the first. Then I began to drive it around limiting the throttle end point 25% for a tank or to, lean the LSN an hour drive around at 50% enpoint , 75%... gradually leaning out the LSN and loosing the foil trying to get the temp at 230. The second motor I was more aggressive going to the driving and leaning process a little earlier. I did notice the pinch and then compression disapeered faster with this method.


Sometimes running it rich to get the lubrication (since the metal on metal pinch is still there) I dont get the temps I want for heat cycling. So I'm guessing the foil should still be on there to get the correct temps is the better method. This is where my patience may be failing as I begin to tune leaner and begin to rip around our practice track especially with the second engine.

So from what I've read here I should be taking it easier on breakin.

Questions:
1)How many tanks should I simply idle through it?
2)What temps do you guys(the guys getting 7+ gallons out of a piston/sleeve) run until the pinch has reduced to race level?
3) How are you getting those temps while breaking in, foil? leaning hour by hour on the LSN?

Sorry I wrote you guys a book, but I appreciate all the advice