Originally Posted by GREGORY!
one off topic question.
what do you do in your motors?first picco's then rb that you have not run in right.
Not sure what you are asking.
But I'll answer the way I see how it is asked.
First engine was a modified Picco Evo3.
Then when that went out, I tried a stock Evo3. That went out the window even faster than the first one!! (2 months or so)
Then I got an RB T10 - absolutely loved the power and tuning of it! Actually had to make it rich (either the bottom or top) to make it more controllable.
BUT, with these engines, I thought I had broken them in correctly, but I didn't monitor the temps/keep them high enough after the 3-4 tanks or so, so I believe it started off well but then because the temps were not high enough to break-in properly, it actually messed them up by basically doing this:
Because the sleeve expands faster than the piston itself, in the beginning it was fine/where it would probably be at it's maximum diameter. After the 3rd/4th tank, that diameter was naturally reduced due to the lower temperature and because it was much tighter, the piston probably wore away too much of the sleeve and so the ability to create a seal was lost once more heat got into it.
Now that I strongly believe that this is the case, I swapped out the unmodified sleeve from the 2nd Evo3 and used the piston from the first modified Evo3. The sleeve was just as tight as a brand-new set, and now I am STILL in the process of getting rid of that pinch. I still can't turn it over by hand without hitting the pinch almost at TDC and this is now the 4th tank since "Frankensteining" it. Plus I modified the stock sleeve using the same measurements from the first Evo3, but I increased the timing on the boost port (by mistake, but it sure does fly!!!)