I was tuning up my ignition system and replacing spark plugs when I noticed the current plugs where not what the manufacturer spec'd. I've got GT40 X305 heads that call for Motocraft AGSF-32C. I'm currently running ASF-42C, which are one step warmer and have half the # of threads on them. Which also means they are half as long from tip of the plug to the seat.
Th previous owner had the heads installed by a shop and as far as I know the heads have not been modified. But I'm a bit chicken to swap to longer plugs in case there was a reason for using the shorter ones. (ie. interference w/pistons). So I've got 3 questions:
1) What is the best way to check for clearance?
2) Could too short of a spark plug cause engine problems, such as misses at higher engine load?
3) Am I just over thinking it and should swap in the plug the manufacturer calls for?
Thanks guys
Th previous owner had the heads installed by a shop and as far as I know the heads have not been modified. But I'm a bit chicken to swap to longer plugs in case there was a reason for using the shorter ones. (ie. interference w/pistons). So I've got 3 questions:
1) What is the best way to check for clearance?
2) Could too short of a spark plug cause engine problems, such as misses at higher engine load?
3) Am I just over thinking it and should swap in the plug the manufacturer calls for?
Thanks guys
