I ordered some e3 plugs and they are e3.42, which is supposed to be right, but I pulled one of the old plugs and it is an autolite platinum ap45. What is going on here?
spark plugs like the e3 are a waste of money. what ever gain they give if any doenst make up for the high cost. as for the part number difference, i dont know if e3 uses the same numbers as autolite. they are 2 different company's and most likely use different numbers. i recommend getting plain autolite copper plugs
The e3 plugs I bought were $5.99 each. That is cheaper than many plugs. Plus they have a guarantee. I guess the question I should be asking is, are Autolite AP45's the right plugs for a 302?
I had AP45s in the 302 in my Comet before. I might be crazy, but the engine seemed to idle smoother with those than with the Motorcrafts I have in there now.
Was that in stock heads? E3 , is saying the e3 42 is the right plug if heads are stock, but the A45 is like 3 sizes bigger in diameter.
the 302 had 2 different size spark plugs. the easy way to tell which one you have is to see what size socket the plug needs. if its 5/8s or 13/16s. if both plugs use the same size they will fit. there are other differences in spark plugs. most important is the heat range of the plug. thats the only other difference that you may encounter but you most likely notice if you got a different heat range.
Is that the socket size or thread size difference? Because they are completely different thread, and it sounds like Bryant was saying socket size?
he was referring to the socket size. But the thread size is different. You got the wrong plugs. Return them if you can and just buy some regular copper autolites 45. No need to spend any more than that on a plug.
The large plug is a 13/16 hex 18mm thread The E3 is a 5/8 hex and 14mm thread In 74 ford switched from the large plug to the small plug
X2 on this Plain jane Autolite copper plus works as good as anything else on the market. Platinum plugs are designed only for those ignitions that fire twice, once on the firing stroke and again on the exhaust, the spark jumps backwards from what I understand on the exhaust and the platinum gets tossed back and forth between the electrodes. Don't know how true that is, but it sounds logical.
Never go by " what was in there "! Go by the charts for what engine and mods you have. Summit has one and I think Jegs does also!
the platinum plug is for long life. the double platinum plugs are for waste spark systems. they fire one plug from center electrode then the other from the ground strap. platinum doesnt wear out nearly as fast as copper does. thus it doesnt have to be changed out nearly as often as a copper plug does. platinum has a much higher resistance than coppers so it doesnt allow for as big of a spark that copper does. iridium plugs are supposed to be best of both. long lasting and allow for a big spark. there was a autolite spark plug tech who answered some questions about spark plugs and he really was pushing iridium plugs. he was supposed to send me a set to try out but they didnt have an application for the larger plug.
