LSOSGT1109
Full Access Member
I finally got around to checking the timing on my IP. I replaced the injectors last summer and athough I had a used but in new condition Snap On MT480 meter complete with the lumey probe, I didn't check the timing at that time. I just advanced the timing until it sounded and felt right to me. When I checked it with the meter yesterday it was at 2* ATDC. From reading Mel's info on timing, I understand that when using the lumey/mag method it should be at 5*. I also understand that rotating the IP toward the passenger side advances the timing and toward the driver's side retards it. I went out today to adjust it to get the 5* ATDC. I rotated it a little farther toward the passenger side and came up with .5 to 1 ATDC at 1400 rpm. So then I rotated it back toward the driver's side to the point where the static timing marks were even, or so close to even that I couldn't tell if they weren't. When I checked it this time I was getting 4.5 - 5* ATDC. So I'm confused, did I acutally further advance the timing to get it to where it's at now or did I retard it? In other words is 5* ATDC more advanced or more retarded than 1* ATDC? I understand that 5* BTDC is advanced from 1* BTDC, is ATDC just the opposite?