my motor has 250000km on it and the compression is just now below spec(133psi) 129psi. i was wondering what was involved in a rebuild if i get a kit im have attened sait for automotives and am quite capable but i was wondering about getting the block machined etc. what would i need to have done that i couldnt do in my garage? im a newb in this so anything you know about doing a rebuild let me know