I need to get advice on which plug to use for a stock '63 401. I searched the forum and what I gather is that AC no longer makes the original heat range plug but still sells one that's one range colder. What about the other manufacturers out there? Any recommendations with part numbers would be appreciated.
Just use the AC plug that is available. That's what I'm using on my '63. Runs great! The worst that will happen is that it will foul a bit sooner than the hotter plug will. No big deal. With lead-free fuel used today the plugs last longer now than they ever did in '63.
No Ford bashing here, I own a few of them. No problem using Autolite or Motorcraft in the Buick just as long as it's the correct part. Ford IMO has always sold good quality maintenance parts.
I have ran the autolite 85s for a while and they worked very well for me. I have just changed over to a Bosch platinum plug last year per Tom Ts. recommendation. I can get the number for you later, they are working well also.
That #4236 is the stocking number at NAPA. The actual plug # is WR9FP. What I like about them so much is that they are a multi-heat range plug. Also being Platinum they require 1/2 the normal voltage to fire. This means, using all the same ignition components, you can open up the gap from the normal .035". I use .045"-.050" on mine with no adverse problems.
On the Bosch plugs, if I have changed over to Crane electronic ignition, should I gap them bigger than .050? Thanks Dan
I wouldn't bother. After a point, I don't think there's much advantage to increasing the gap. What gap does Crane recommend? I don't know enough about the internals of the Crane system to know what voltage and energy they are throwing. Do you keep the stock coil with their system? Jim
If by Crane electronic ignition you just mean an electronic pick up in lieu of points that has nothing to do with the voltage output etc. Also you will see a lot written about Autolite spark plugs breaking off flush with the hole during removal. I had to remove the head on Ford Industrial engine just to get out the base of the plugs. It was not my idea of a good time.
Hello Jim. I`m pretty sure that car came with 44S AC plugs. I have a set of 8 I can part with. They are the newer type R44S. These are even discontinued to the best of my knowledge. R is resistor which suppose to cut down noise in the radio. mrbuick65@rogers.com John
Jim. I just noticed a guy on Ebay selling R44S sets of 8 plugs for 8.50. That`s cheap. I won`t sell mine that cheap. He has 4 sets available. The item # is 170191506858 John
Jim. I see the guy sold all 4 sets. I am assuming they are yours now? I see them on Ebay periodically. There is a guy who is always at one of the car swap meets in my area that has a couple of sets of them. They are AC 44S. They are brand new and say Fire Ring on the package and are made in England. I guess AC had a plant there at one time. Maybe I`ll pick them up in the spring. Good luck, John
Yep, I picked them all up. At $8.50 a box, I figured it was too good of a deal to pass up. And if need be, I can always turn around and sell the one's I don't use. I still might play around with the platinums like Tom suggested though. He knows the Nailhead better than me so any advice he gives out I am sure is good. The 44S's and the R44S's are basically the same plug except for the resistor rating, right? I even read in the service manual that 45S's could be used if the car was driven mostly at low RPM's but high speed driving could possibly cause piston damage with this plug. Again, I am very grateful for your help. :beer
