Oh no what have I done

[Rodney Bullock]

I changed my plugs today, went to AC R45, my car ran like crap. it would not rev up or anything. Luckly I did not throw my old plugs away. I cleaned them and put them back. My car ran great again. my question is this: The plugs I am using are champions they are not resister plugs. The plugs I have has a long electrode, maybe I am using the wrong technical name. The white part at the end can be seen. The AC plug can not, does Champion have a resister plug with a long end. By the way the radio played excellent with the AC plug no "frying Bacon" sound" I got to get the right plug for this summer. The 6cly is in!

[Norm's Coupe]

Rodney, you can get long or short plugs in any brand plug. Maybe the engine in the 40 doesn't take AC45. To switch from Champions to AC's, just have them look up the cross reference at the parts store to get the right number plug. The numbers on the plugs will also give the proper length.

[Rodney Bullock]

I got some R45S plugs today, they are long.

[claybill]

hey rodney...this is a hot topic you are onto...

AC plugs have the electrode flush with the threads of the plug. the champs have the electrode extended out..concequently they reach further into the cyl for better combustion. ( so they say)

on my new fenton head the metal casting was thicker and i needed a longer plug reach. look at the past topics about 'plugs...fenton' lots of good advice there, just last week.

so....why are champions not the favored plug of our group????

i bought new AC425 a longer reach plug for the ply. i have a 41 coupe.

claybill

[Powerhouse]

I run with AC R45 in my 53 dodge truck engine....runs ok....

Does the R45S work as well as your old Champs?

[Rodney Bullock]

Ok here is the deal, You can get any plug (almost) in the short and long version. The R45 is a short plug. The AC R45s is a long plug. I have Champions in my Studebaker RJC8 they are long in all my cars there are long plugs, I checked last night and found that I have AC R45S in my 53 chevy truck so we can safely say that the long plug is the better plug. OK now if your head has been milled or your block has been decked you may be able to use the short plug. I tryed to use the short plug when I was rebuilding my car and could not get it to run consistant. I stumbled onto the long plug. We now must find out what these pre and suffixes mean. The S means long in Ac while the R with Champions means long while the R45TS is a different size plug altogether(small) for v8's:mad: what am I to do!

[martybose]

(snip)

so....why are champions not the favored plug of our group????

(snip)

When we were dragracing Champion provided plugs, and we changed them weekly. When they stopped supplying them we went with Autolites, and rarely changed them at all.

YMMV.

Marty

[laynrubber]

Something to watch is that spark plugs are fragile with their high pressure porcelin construction. I have seen the kid at the local hardware store kicking boxes and packages of plugs around a little rougher than they should be.

In aviation when we drop a plug it goes in the garbage ($50 or more a plug).

Maybe you have a couple bad plugs that have damaged porcelin ?