Question: Spark plugs

[Hib Halverson]

"Wrong" is fine with me..."incorrect", "mistaken" or whatever.

I'm still trying to figure out what about my spark plug post was wrong–maybe it was was this...

The 43 is the spark plug I'd recommend for a 66 327 which is driven normally. It's a really good heat range for the high-performance street driving duty cycle.

I sometimes use the word "normally" when talking about driving Corvettes and make the mistake of choosing my words from the perspective of how I drive my Corvettes. Other people might use the term "aggressive" or "hard", so...for "65TripleBlack's" benefit, let me restate...

The 43 is the spark plug I'd recommend for a 66 327 which is driven aggressively. It's a really good heat range for the high-performance street driving duty cycle.

 

[Vettehead Mikey]

I don't know if any 1950's or 60's SBC Chevies were ever delivered with AC 43 plugs installed. I doubt it, but, maybe the '67-'69 Z28 might be the exception if, in fact, what you intimate is true.

Tripped over this info while looking for something else:

1969 Corvette factory installed plugs.

base engine R-44
L46 R-44
L36 R-43N
L68 R-43N
L71 R-43XL
L88 R-43XL


Why can I remember irrelevant info like this but not what I did two minutes ago? :L

 

[65TripleBlack]

Tripped over this info while looking for something else:

1969 Corvette factory installed plugs.

base engine R-44
L46 R-44
L36 R-43N
L68 R-43N
L71 R-43XL
L88 R-43XL


Why can I remember irrelevant info like this but not what I did two minutes ago? :L

I think I had eggs for breakfast this morning but don't remember whether or not I had breakfast this morning.

All those engines using 43's are BBC's. I said that there were no SBC's that used 43's, as far as I know.

 

[vigman]

Correct me if I'm wrong here....

Assume we're talking about Joe average owner with a high milage ( read slightly out of tune ) weekend cruiser. Wouldn't the factory recommended plugs be a starting point? Wouldn't one want to read the plugs to decide what actual heat range would be optimum for the engine wear, bolt on mods, altitude, jetting, quality of fuel ( and or additives like TURBO IN A CAN 9000 ) timing and exterior temp ? Or are we talking about what's NCRS correct?

Mike

 

[JohnZ]

Assume we're talking about Joe average owner with a high milage ( read slightly out of tune ) weekend cruiser. Wouldn't the factory recommended plugs be a starting point? Wouldn't one want to read the plugs to decide what actual heat range would be optimum for the engine wear, bolt on mods, altitude, jetting, quality of fuel ( and or additives like TURBO IN A CAN 9000 ) timing and exterior temp ? Or are we talking about what's NCRS correct?

Mike

I think you'll find that any standard plug in a 45 heat range (AC 45, R45S, etc.) or any plug that crosses to the AC 45 heat range (like Autolite 86, Champion RJ-14YC) will work fine for a cruiser.

 

[ratman]

correct spark plugs

little late / R45XLS 66 L72 no fouling of plugs 3k street driving

 

[haganml]

Interesting thread, got a little "sparky" though.

Mark.

 

[vigman]

Well since this resurfaced

It looks like 43's, just add an MSD blaster..LOL~

Corvette Spark Plugs C1 Replacement for AC44 Set of 8 | eBay

 

[JohnZ]

It looks like 43's, just add an MSD blaster..LOL~

Corvette Spark Plugs C1 Replacement for AC44 Set of 8 | eBay

Dunno why they describe R43's as a "replacement for AC-44's"; THEY'RE NOT. 43's are WAY too cold for normal street operation. Run those on the street and you'll learn all about plug fouling. :eyerole