Deseminated from the Schrick Camshaft Catalogue
http://www.avl-schrick.com/dat/MK/Schrick%202009%20E.pdf Page 1 of it...
Valve Timing degCRA
IO-IC-EO-EC
17-55 71-25
Valve timing is shown as IO (Inlet opens in
°Crankshaft before TDC), IC (Inlet closes in
°Crankshafts after BDC), EO (Exhaust opens in
°Crankshafts before BDC) and EC (Exhaust closes
in °Crankshafts after TDC).
Therefore without drawing a diagram, it's...
Inlet Opens 17deg before TDC.
Inlet Closes 55deg after BDC.
Exhaust Opens 71deg before BDC.
Exhaust Closes 25deg after TDC.
TDC -BDC being a vertical line. TDC being effectively 0deg, but note the IC and EO valve degrees are taken from BDC. If ive got that correct.
So a 42deg valve overlap duration during TDC and a 126deg valve overlap duration during BDC.
that make sense?