I found out today that I am currently running Champion RV15YC4 plugs. I want to change them because it's been a couple of years since they were put in. Are these good plugs or should I try something else? This is for a 1958 283 block w/ HEI from a 1983 Blazer.
Here are the specs on the Champion RV15YC4: Resistor plug, 14mm, .460 " reach, taper seat, 5/8" hex head, projected tip, copper core I suppose the "reach" is the gap? Champion lists these as fitting a 1970 Malibu w/ 7.4L V8 (I suppose that's a 454). Thanks, John Nasta
