Originally Posted by
.rc_racer
i just got a arrow i just want to make sure that i am doing this right...First i am going to break it in with the enclosed break in shim. I am to run the motor WITH the shim in it for 1 gallon, after the first gallon i am to take out the break in shim and re adjust the tune on the motor and let er rip correct?
Install the break in shim no matter what nitro percentage you are using. Start with a P3 plug. Do nor remove the extra shim until the nuts drop and the engine is ready for full out race tune. Some people have gone more than a gallon until that happens. You will know when the mecahnical pinch is gone because your tune will go rich and your temps will drop. Remove the extra shim, change to a P4 plug for optimum performance and retune from there.