[bob d]

I need to know the cross reference no. for r44s to ngk spark plugs. Thanks Bob.

[John V.]

Can't vouch for the chart, but look here. Easiest way seems to do a CTRL F and search for R44S.

http://www.angelfire.com/extreme4/sk..._REFERENCE.htm

Google search shows various guys using a variety of NGK plugs as subs for the R44S.

The R44S has an extended tip (S) and is a resistor plug (R). If that is the style you want, the Chart probably will provide what you need.

Same as AC, NGK offers different tip types and various heat ranges.

I have AC in the '64 GTO, have been using Autolite in my daily drivers for a lot of years now. Only experience with NGK has been in my Honda mowers.

Back in the late '90s, I got a shop tune-up in my Taurus daily driver. They put Bosch in. In short order the car ran like crap. They found a supposed "bad" plug and replaced it. It soon ran like crap again. In frustration, I did my own diagnosis. I discovered that the terminal tip was screwed on and the tips were getting loose. That caused an intermittent miss. I replaced them with Autolite and it never missed again. That experience had me swearing I would never use a Bosch plug again.

While searching I found a couple guys claiming immediate performance gains when they switched to NGK.

Just curious, are you looking to go with the NGK for performance reasons? What is the application?

Would like to hear how they work out for you when you make the switch.

[bob d]

Thanks John. I was just looking for a different plug to try. What is the autolite crossover for the ac r44s plugs? Thanks Bob.

[John V.]

You can check the same Chart I linked for the Autolite cross.

But according to what I read elsewhere, the Autolite listed is discontinued.

However, if you go to the Autolite site, you can plug in R44S there and 2 choices come back, their best iridium choice or the cheaper copper.

https://www.autolite.com/parts-finder

Plug R44S into the Competitor's Part No. box and it will spit out the choices.

[bob d]

Thanks John for the information. Will try the autolite plugs. Thanks Bob.

[Geoff]

BPR5S are the correct NGK plugs. BP5S if you want non-resistor.

[chrisp]

Call NGK tech # , they are very knowledgeable.