Hey, y'all. I've searched a lot of threads, but haven't found anybody with this exact problem. Besides, it'll give you an opportunity to laugh at my pain.


As we all know, the AC R44S plugs that sparked many of our beasts (including mine) are no more -- discontinued by the factory many years ago. I've been using R45S's and other Brand X cross-reference variants (Champion, NGK, Accel, etc.) and they've been mostly okay. But in the last couple of years, the engine has developed a light pinging at part throttle, so one of the ways I want to try to combat this is with a colder plug. But the only readily available alternative from AC is the R43S, which everybody on the interwebs seems to agree is WAY too cold to run on the street.


So, just for kicks and grins I called up my local Mom 'n' Pop parts store, and lo and behold, they had some R44S's way in the back of the shop gathering dust on a high shelf. The boxes were so old they actually said "Made in USA" on them! Twenty-five bucks -- how do you go wrong? I'll tell you how: they only had seven of them. I bought them anyway, figuring I could either find an orphan R44S somewhere, find a Brand X cross-reference to use for an eighth plug, or flip the damn things on Ebay if neither of first two plans worked out.


Well, it seems kind of like overkill to go to Ebay and go through the whole shipping thing to buy one spark plug, and besides all the lots I saw there were sets of eight. So, it was back to the parts store to find a cross-reference equivalent. Long story shortened (at least a little bit; stay with me here, we're nearly done) none of the other brands that cross reference to an AC R44S look ANYTHING like the R44S's that I have. Different reaches, different hexes, shrouded electrodes, weird extended tips, you name it, NONE of them was the same.


So, does anybody know what is the proper cross-reference for an AC R44S? At this point, I don't care what brand -- hell, if they look more or less the same I'll try one even if they're made in Tierra Del Fuego for J. C. Whitney.


Conversely, if anybody has a single R44S that they'd like to part with, I'm all ears.

 

Your going to have to find another R44s, which as you found out is not easy. I think your going in the wrong direction, it's a timing issue. Check your total timing with vacuum advance and see where it is at around 3000 rpm. I bet it's too far advanced, over 52.

 

Thanks, Eric. We've been down that road before, a whole other thread's worth, so I thought I'd try a different tack. Besides, I need new plugs anyway.

 

I have had 3 orphans looking for another 5 for several years.
I thought they were made from unobtanium. 4 stripes, knurled bases.
Make me a nice offer and they are yours.

Edit: Mine are the 44S non-resistor. Oops, didn't mean to get your
hopes up like that, apologies.

 

Well, the resistor thing may not be a deal-breaker. I'll keep them in mind. Thanks.

 

Well...I was looking through my others and found a beauty.

 

You said in your other thread your using 91 octane, is there 93 available?

 

You may be thinking about a different thread. We have ethanol-free Chevron 94 'round these parts and that's what I've used since I've had the car, so I consider myself lucky in that regard.

 

Very interested. What would you need to make it worth the effort? Keep in mind (just to add to the PITA factor) that I'm in Canada.

 

PM sent.

 

Well, we have already been down this road , but your '69 400 engine, if it is nearly stock, was designed for Super Premium fuel (by virtue of it's compression ratio), such as Sunoco 260 LEADED, advertised at the time as 103.5 octane. To my knowledge, there is nothing available locally that even comes close to that!

As a longtime Olds driver, I went through this with two '70 442's with 455's, and a few others before them, (including two Mopars, a '69 383 HP and a '71 Duster 340), all high compression engines requiring PREMIUM fuel; I used to use Sunoco CAM II racing fuel mixed with premium unleaded, or Avgas lowlead similarly mixed. Also used Reallead tetraethyl lead additive as an octane booster; today's octane boosters available off the shelf are mostly alcohol concoctions only aggravating the problem, not solving it!

I also used Champion UJ10Y plugs, or J63Y and J61Y racing plugs, for a cooler heat range! The main problem back then was plug glazing of the porcelain from lead deposits from the fuel, not pinging from low octane fuel!

This link MAY help.....don't know!??

http://www.imps4ever.info/tech/engin...ark-plugs.html

 

This may no longer be needed, but here are some supposed cross overs:
Replacement spark plugs for AC DELCO R44S:

• Accel 0437
• Accel 138
• Accel 437
• Accel 437S
• Accel P437
• Accel R44S
• Autolite 3224
• Autolite 3225
• Autolite 3226
• Autolite 3227
• Autolite 565
• Autolite 84
• Autolite 85
• Beru 14R-11F
• Bosch WR10F
• Bosch WR8FC
• Bosch WR9FC
• Bosch stk 7516
• Champion OJ11Y
• Champion OJ12Y
• Champion OJ13Y
• Champion RJ11J
• Champion RJ12Y
• Champion RJ12YC
• Champion RJ12YC6
• Champion RJ13Y
• Champion RJ14J
• Champion RJ14Y
• Champion RJ14YC
• Champion stk 63
• Denso W14PRU
• Denso W16PR-U
• Denso W16PRU
• Denso W20PR-U
• Denso stk 3037
• Denso stk 5046
• General Motors 5613866
• Mighty M4R52
• Mopar 2444870
• Mopar 2642475
• Mopar 3438334
• Mopar 4091936
• Motorcraft AR42
• Motorcraft AR52
• Motorcraft AS42C
• Motorcraft stk 49
• Napa X701
• NGK 2637
• NGK 2990
• NGK 7055
• NGK BP5S
• NGK BPR4S
• NGK BPR4S-15
• NGK BPR4S-20
• NGK BPR5S
• NGK BPR5S-15
• NGK R5670-6
• NGK XR4
• NGK XR40
• NGK XR45
• NGK XR5
• NGK stk 2746
• NGK stk 3332
• Prestolite 14-32
• Splitfire SM008E
• Torch G5TC
• Valley Forge 44R

 

Thanks very much -- it will definitely help, as the only model number nomenclature I really understand is AC. Probably why I keep buying them.


You're right about the 94 gas not being enough. I use an octane booster too.

 

Thanks, Ozzie. That looks like the same list I've been using and the problem with it is that most of the plugs on there don't look anything like an AC R44S. The main criterion seems to be whether the sparkplug will screw into the hole!

 

Anyway, looks like Tru-blu has one for me, so problem solved for now. Thanks, everyone!

 

Olds itself recommended 43's for high compression engines that saw mainly highway use and regular hard acceleration as that would keep the lead deposits burned off. The caveat in the shop book did say lead fouling would occur if these plugs were used putting around town at low speeds. I proved that with a 64 Starfire running a 30-70 mix of 100LL Avgas and 93 unleaded.

If you've been using 45's they are a little hot for today's so-called fuels. Are you on points or an electronic unit?

 

HEI. I gap them at 0.045