FSI Spark Plugs: AC Delco R45XLS - HELP

[sandbug]

I am running Autolite 3076 spark plugs on my Model A
('32 B Engine, high compression head, alternator, 12V, FSI, Headers, Stromberg 97).

I'm getting some pre-ignition knocking, so I am in communication with FSI to adjust the timing.

I decided to get some cooler plugs, so I went onto the FSI site and bought a four-pack of AC Delco R45XLS plugs. It says they are 14mm resistor plugs, better than Champion W16 plugs,and I didn't know the Model A uses a 7/8" thread plug.

My son's '30 Coupe has 7/8" thread plugs, and it's all standard in that area.

Are there any Model A heads with a 14mm plug?
Can I find and add a thread sleeve to make a 14mm plug work?

I've got a call to FSI, but Oklahoma time is different than California.

 

[Synchro909]

It sounds like you need a set of these. https://www.snydersantiqueauto.com/product.htm?pid=984102&cat=41743
Using modern, readily available plugs saves a lot of hassle. I made a set of adaptors for one of my cars but I think that when I need to replace the plugs in other cars, I'll use these.

 

[Doug Linden]

Snyder's stocks 7/8 to 14mm adaptors. Give them a call.

 

[sandbug]

Thanks!

 

[ModelA29]

Standard was the 7/8. 14mm is the more modern plug and also used in many of the aftermarket heads.


I can't understand using a resistor plug in an A. As have no electronics to interfere with. It's also puzzling that FSI says to use resistor plug wires when the stock Model A plug connectors they supply are solid brass.

 

[katy]

The resistor plugs and/or resistor plug wires are to reduce RFI, maybe RFI interferes w/the FSI ignition.

 

[Big hammer]

The resistor plugs and/or resistor plug wires are to reduce RFI, maybe RFI interferes w/the FSI ignition.

That’s what they are concerned about FSI , along with don’t leave it no longer than 30 seconds with the engine not running, and very clean electrical connections