Sparkplug Length
Thread Starter
Burning Brakes
Joined: Jul 2001
Posts: 862
Likes: 0
From: CT
Sparkplug Length
Just bought a new set of ACDELCO plugs #R45TS. When I removed my old AC plugs (same numbers) they are about 3/16 of an inch shorter. Whats up with that? Is this going to make any difference? Are there two types of ACDELCO plugs with the same number? Any help would be appreciated.
Thanks
Mike
Thanks
Mike
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
I believe you are speaking of the porcelain end and not the extended electrode tip. I have seen this before when I had my 1979. I do not know the reason but I can assure you that no change in performance is the end result. But it is curious. It might be a result of AC Delco outsourcing its spark plug production to non-USA suppliers such as NGK. But that is pure speculation.
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Mike,
I'm cashing in for the evening so will leave this one in the hands of others. I don't recall the threaded area of the plug being longer. But again I will leave that with more informed opinions.
I'm cashing in for the evening so will leave this one in the hands of others. I don't recall the threaded area of the plug being longer. But again I will leave that with more informed opinions.
Le Mans Master
Joined: Mar 2004
Posts: 7,493
Likes: 1,502
From: Little Rock AR
What you need to look at is the length from the "seat" on the plug. The distance from the tapered seat to the farthest end of the thread dimension should be the same. The extended tip is not part of the thread, it is part of the insulator/electrode.
If the threads will protrude into the chamber, this is bad. If the threads will not screw in all the way, this is bad too.
-Mark.
If the threads will protrude into the chamber, this is bad. If the threads will not screw in all the way, this is bad too.
-Mark.
