Originally Posted by
Sylvain
Any one uses an extra head shim?
Yes, after break in... if you run in a "normal" climate. It brings your compression up (replace the two shims under the head with the extra one you get in the package). In high humidity and high air density conditions you may want to stick with the standard shimming.
After break-in, you should also switch from the included RT3 plug (if you used that) to the RT4/P4.