I'm in need of some new spark plugs for my 455. Anyone have any good suggestions on the best type plug?

 

A/C Delco R-45S if you can find them.

 

Okay thanks I was looking at some ngk and I didn't know how well they would be.

 

Get the NGK plugs in your heat range. AC Delco aren't what they used to be.

 

How exactly do you go about knowing what heat range?

 

Cross reference this number to an NGK.

 

NGK Iridium work best.

They have a cleaner idle, and you can feel the difference with them.

And, yes, I have tried everything out there.

 

Okay, so AC isn't what it used to be -- their plugs are no longer made right there in the plant in Flint, Michigan...... at least they took their own equipment down to Mexico.... still think it is far better than a Japanese plug that has no business being in a ----- REAL AMERICAN CAR !!!!!!! -----

But that's mine and 200,000 other Americans opinions.............

Call me, I'll let you know what the book says is the correct heat range --

Craig -- 516 - 485 - 1935.... New York.....

 

Okay thanks for the in put. I'm gonna try the NGK and see how well they work. Anything has got to be better than what is in it now.

 

There is an Autolite, (Fomoco) plug
that is every bit as good as the R-45S.
I believe it is an Autolite 46? Does that sound right?
It is the Ford equivalent of the A/C R-45S.

I have not run them in a while, but they are excellent,
made in the good old USA. ( I hope.)

 

I run AC Delcos in my Olds. They work great.

 

NGK, while having U.S.-based operations and manufacturing facilities, is a Japanese-owned company.

Autolite spark plugs are now made by the same company that makes Fram filters and Prestone antifreeze, and the company is New Zealand-based.

 

Is it better to run a resistor plug or non resistor one.

 

NGK's website says this about resistor plugs. They're basically saying you should use nothing but.

http://www.ngksparkplugs.com/techinf...aqresistor.asp

 

I found some NGK resistor plugs pretty cheap on eBay. Would they be O.K. to run in my 66 442 with stock ignition?

 

Okay so basically a resistor plug is the only way to go.

 

Anything but champion..what a horrible name for a pos plug..ac or ngk for me..they are easy to locate.

 

Okay. What about accell plugs?