Effect of spark-timing regularity on the knock of engine performance (1938)
NASA Technical Reports Server (NTRS) · leaf 7
Fig.3 N.A.C.A. Technical Note No. 651 … maximum engine performance with incipient knock Spark dispersion for A was within^5 crankshaft degrees; for B,within£ -5- crank- shaft degree*
NASA Technical Reports Server (NTRS)
Internet Archive · NASA Technical Reports · Public domain (US government work). Free to use for anything.
