Everything posted by mfd
Your engine sounded like mine after I had changer the plugs. I used my Haynes manual to put the wires back on. That manual had 5 and 6 backwards for my 351c. luckily I have reproduction ford manuals for my 71 m code, and it showed the proper orientation. After I corrected the problem no backfire thru the exhaust, and I was able to finish the tune up.