The present invention relates to a method and devices for identifying {HEAD ~ which cylinder} is in {TAIL ~ the compression phase} 
is in
The present invention relates to a method and devices for identifying { HEAD ~ which cylinder } is in { TAIL ~ the compression phase }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL