Spark plugs

[john fotakis CLC#23436]

Hello everybody. Hope youre all cruising trouble free. My question today. I know type 44 spark plugs were originally specified for a 1961. I have a set of type 45s [ its always the way isnt it? ] Can anyone foresee any problems with using these?  Cheers, John.

[Phil Whyte - CLC No. 14192]

Hi John, if its any help when I was last in the USA i tried to buy 45s for my 54 Cad and all that was available was 44s . I was told that that was what AC recomended. If you are in the UK like myself I would be prepared to do a straight swap with you [Ill have to check Ive got a set of 44s still though]. I only use AC plugs as Ive found other makes give up early in Cad engines. If you want to use your 45s I think they should be fine , they should be short reach.
Phil

[John Washburn]

Folks,

The AC 44 is on the lower end of the heat range, the AC 45 is one step hotter, and the AC 46 is the high heat range.

If your plugs are running clean, no black around the edges then I would stay with the AC 44 (you see them all the time on e-bay), but if they are not burning all the fuel, some black, then you might consider the AC 45.

John Washburn
CLC #1067

[john fotakis CLC#23436]

Thanks for the replies guys. One more little fact for the memory box [as Bruce might say ] . Thanks for the offer Phil, but I may as well use the ones Ive got now. Cheers, John.

[Roger A. Zimmermann #21015]

I was told that the AC 44 spark plugs are no more available?
Therefore, I will look at ebay, even if I dont like that system...

[Phil Whyte - CLC No. 14192]

No longer available , thats terrible. I saw sets of 8 for sale in K Mart a cuople of years ago, but K Mart was in trouble then - has it gone the same way as AC 44s ? !!!!
Phil

[Roger A. Zimmermann #21015]

Phi, its not that terrible! I saw a lot and bought some when I had to go in the States about 15 years ago.
On an old (1989) AC-Delco catalog, the type 44 or R44 does no longuer appear; they are replaced with R45S. I dont remember exactly what I installed in my Cadillacs; probably something colder like R43 as we drive in Europe at higher speeds than in the USA, even with older cars. It sould not be a bad choice as the color of the plugs is OK.