Timing issue after replacing spark plugs & wires?

KingofThings

Veteran Member
May 8, 2020
403
I can't take credit for that "article". I found it by searching the WEB and reading through several pieces/posts on your potential problem. Many of us from the "older" group have dealt with the same problem - even when these cars were relatively new. That "article" summarized several of the fixes I've found over the years and described the potential causes - but thanks for the thanks.
What matters is that you cared enough to help and bothered to find and post it. :)
 

mikeadd

New Member
Feb 8, 2012
2
Eastern Shore
My Z28 is a 1971 but it has a newer 350 engine in it (maybe a late '70s). I just replaced all 8 spark plugs and wires. I put in the same brand and type that it had before from the previous owner (Accel 276S spark plugs and Accel 8mm hi-temp wires). Before the replacement I think the engine had a timing issue (it kept misfiring for a couple of seconds after being turned off). The hotter the engine was the more it would misfire. Now with the new spark plugs and wires it is more accelerated at idle speed, it now backfires through the exhaust pipes when I push the throttle, and the throttling is not as strong as it used to be (it doesn't rev up the engine as much). The gap that the old spark plugs had was somewhere around 0.032 inches. The gap that I set in the new spark plugs is 0.035 inches. Can someone shed some light on what's going on and what do I need to do to fix this? Thanks in advance!
Back in the 1970s I remember that the new resistor spark plugs for the z28 motors were R43 or R44s, Back then if you dropped them they would not work anymore. Also the centrifugal advance weights in the dist would freeze up cause the problems your having.
I sold my 72 z28 rally sport in 2012 and still regret it.
 

KingofThings

Veteran Member
May 8, 2020
403
Back in the 1970s I remember that the new resistor spark plugs for the z28 motors were R43 or R44s, Back then if you dropped them they would not work anymore. Also the centrifugal advance weights in the dist would freeze up cause the problems your having.
I sold my 72 z28 rally sport in 2012 and still regret it.
I used to use exactly those and still have some around!
 




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