Spark plug experts

[Edbert]

So, should I just buy whatever plugs the instruction manual for my heads (non-smog perf-rpm) say or do the various gurus and experts that hang out here have better recommendations?

My cam specs are in the sig as is my ignition, my cr is about 9.5:1, I intend to run 87 octane. Anything else that would effect the choice?

I'm going with the stock timing of the pro-billet distributor out of the box, any recomendations for a starting point on the gap?

 

[rbohm]

start with the heat range they recommend, then change as needed. you can use the the plug number they list and have the parts person cross reference the number to your favorite brand plug, it one exists.

 

[Edbert]

I don't have the instructions with me right now, but I know they used a Champion part for their recommended plug. I always used Autolites back when i was daily-driving a classic stang, but I stopped doing that in 1992. I know the platinums are good, but until i get my plugs heat range and gap figured out I don't think I should invest in platinums yet. Are those multiple tip plugs a marketing gimick?

 

[jerry S]

So, should I just buy whatever plugs the instruction manual for my heads (non-smog perf-rpm) say or do the various gurus and experts that hang out here have better recommendations?

My cam specs are in the sig as is my ignition, my cr is about 9.5:1, I intend to run 87 octane. Anything else that would effect the choice?

I'm going with the stock timing of the pro-billet distributor out of the box, any recomendations for a starting point on the gap?

I have your same heads. I corresponded with edelbrock tech on the matter and they said I am best off sticking with Champion RC12YC or equivalent. The guy who built my car said I couldn't do better than the Auotlite 3924 plugs.

 

[rbohm]

edbert, if you are refering to the splitfire plugs, or the bosch plugs that have multiple electrodes, i personally think they are not worth 6$ per plug.

 

[Edbert]

Thanks guys!

best off sticking with Champion RC12YC or equivalent. The guy who built my car said I couldn't do better than the Auotlite 3924 plugs.

Do you know if those two choices correspond with one another on the chart?

edbert, if you are refering to the splitfire plugs, or the bosch plugs that have multiple electrodes, i personally think they are not worth 6$ per plug.

Those are two of the type I was refering to. I can see if your spark it a little weak that might help but my spark should be about as hot as it can take with the full MSD arrangement. I figured they were sort of a scam but wanted a back up opinion

 

[jerry S]

Do you know if those two choices correspond with one another on the chart?

Yes. they are both gasket seat, 5/8 hex, 14 mm, 3/4 reach plugs.

 

[Edbert]

EEEEEWWWWWWW...milimeters!! *&#*^%#@

just kidding, thanks jerry!

 

[HistoricMustang]

So, should I just buy whatever plugs the instruction manual for my heads (non-smog perf-rpm) say or do the various gurus and experts that hang out here have better recommendations?

My cam specs are in the sig as is my ignition, my cr is about 9.5:1, I intend to run 87 octane. Anything else that would effect the choice?

I'm going with the stock timing of the pro-billet distributor out of the box, any recomendations for a starting point on the gap?

I have had good success with the Bosch plugs and would suggest starting with .035 and working up. This deal is kind of like cutting front coil springs..............it is a pain in the butt but well worth the effort.

HistoricMustang
www.historicmustang.com

 

[thehueypilot]

I found an excellent web site for crossing plugs from hot to cold and Autolite to NGK ect. Its safer than relying on the parts counter kids from giving me the wrong plug. Its called Sparkplugs.com