Spark Plugs
 

What plug should I use? .035 gap? What plug wire set is the best for HEI? I would black ones and be of top quality. I have headers and would like them over the top of them and the covers.
Any help is appreciated.
Randy
PS. Changed oil with. Delo 15-40 and a NAPA #1069.
Supposed to have the right levels of. Zorrospp in it.

Am I doing ok?

Randy

Some do jump up to .060 gap with HEI but more common is .045. The larger the gap the more resistance in the circuit. The more resistance the more chance that high voltage is going to find another path to ground. Like maybe punching a hole through the plug wire insulation and crossing to another plug wire or to the block. Maybe even causing carbon tracking in the cap. .060 will work but everything else better be up to the task. That's why newer cars have individual coils right near the plug, less components to brake down while pushing that high voltage around.

What plugs are you running now? There is nothing wrong with AC or even Autolite, I know Ford. I guess I'm not a big fan of $10 a piece plugs. These cars been running pretty strong for over 40 years with standard resistor plugs.

Great. Heads are stock. I hate to ask the kid at Kragen's for the right plug. What number AC should I go for?
Thanks guys,
Randy

I like ACDelco and if your heads are stock I think the part number is R43XLS gap them at .45 they are about $2 a plug. While your at it indexing your plugs are a good idea free hp; a kit from SummitRacing is about $8 and it easy to do.

I can answer your question,but as to not make my knowledge of mechanical crap public and disrupt the entire forum,I will pm you the answer.:p

R43XLS is the stock replacement plug. He should read his current plugs though just to see if he needs a hotter or cooler plug. That's why I asked what he was running now so he could see if the 43 is right for his engine. I'm sure that engine has had some work over the decades.

Also as for the wires. I'm running Accel wires, they're black with a yellow Accel logo in them. Red/orange boots that can be angled enough to clear headers, at least they clear my headers. I know guys that spend a fortune on plug wires or make custom fit ones. The Accels, even the stock Delco's from a early 80's 454 pickup will work good.

I think the Accel's are 8mm. Summit, Accel, etc., it's not rocket science. They're wires with insulation and the boots at each end. The advantage to custom is they're exactly the length you want. I have so many other things to deal with that custom fit is far from the top. Not that it won't work it's way up there eventually.

We can guess all day long whats been done to this engine since he gave no infomations so that's why I said "If your heads are stock then I would run the stock plugs. If the engine is running good with the plugs currently in it staying with the same type of plugs is the way to go; why create a possible problem changing heat ranges if that's not an issue. We don't know if the engine is tired, or for that fact modified and he doen't say why he's thinking of a plug change. To me it sounds more like he wants to know the gap he should be using, not that anything is wrong currently with his motor.

We don't know if he has a spark plug wire cutter crimper, nor if he's worked on an engine before so getting a universal set is easier than trying to cut and fit a non finished set. His setup sounds stock to me with just headders. Going to 8MM on a stock system could drop the voltage to the plugs and why spend the extra money on something he might not need. More info is needed before making anymore decisions. And you are correct this is not rocket science or brain surgery but you need to know the basics configuration of this setup and some of his goals before spending money he doesn't need to spend.

Robert, like you said we don't know what's been done to the engine. We also don't know what plugs he's running now, that's why I asked. Going with the 43's is probably a safe bet but he may actually be changing heat ranges if he does. We don't know because we don't know what's in there now.