Rapidfire 6's or 8's ????

[AWeb80]

I have rapidfire 8's in the GP now....and thinking about getting some new plugs before my bro quits o'rly's...

 

I looked up the GP on acdelco's website and it says I should have 6's for the 3100.....the 8's do just fine...but what is the difference between them?

[19Cutlass94]

#6 is a colder plug than #8.

 

 

The higher the number the hotter the plug

[AWeb80]

#6 is a colder plug than #8.

 

 

The higher the number the hotter the plug

 

so, what exactly is the difference to me....what does that do to my engine?......better/worse mpg, performance?

[19Cutlass94]

#6 is a colder plug than #8.

 

 

The higher the number the hotter the plug

 

so, what exactly is the difference to me....what does that do to my engine?......better/worse mpg, performance?

 

The tip of the spark plug itself is colder or hotter by the center electrode length. Its more of an A/F and fouling thing more than anything else.

 

Heres a couple links with great info on this.

http://www.ngksparkplugs.com/techinfo/spark_plugs/techtips.asp?nav=31000&country=US

http://www.forparts.com/techngkplugrange.htm

[pwmin]

if 8's work, i would stick with them. yes, colder plugs keep the engine running cooler, but warmer plugs actually burn better. you wanna use the hottest plug your engine can take without producing KR or whatever. at least, thats how i know it

 

quote from the articles: "A hot spark plug maintains a higher internal operating temperature to burn off oil and carbon deposits, and has no relationship to spark quality or intensity.

 

Conversely, a cold spark plug has a shorter insulator nose and absorbs more combustion chamber heat. This heat travels a shorter distance, and allows the plug to operate at a lower internal temperature. A colder heat range can be necessary when the engine is modified for performance, subjected to heavy loads, or is run at high rpms for a significant period of time. The colder type removes heat more quickly, and will reduce the chance of pre-ignition/detonation and burn-out of the firing end. "

[AWeb80]

well, i'll ask my bro about the 8's then ...see if orly's has any

[PCGUY112887]

At autozone, if you look up a 3100 GP it lists it needing Rapidfire 8's

[AWeb80]

At autozone, if you look up a 3100 GP it lists it needing Rapidfire 8's

 

huh, strange....ACD's website calls for 6's.

[pwmin]

At autozone, if you look up a 3100 GP it lists it needing Rapidfire 8's

 

huh, strange....ACD's website calls for 6's.

hmm, i looked on AZ and i saw 6's also. 6's are the same heat range as R44's, which are 1 full step hotter than the coldest you can get (R42's). looked on ACD and the TGP got 8's (same heat range as R42), so the 8's are colder than the 6's. im confused, though, cuz according to ACD, my LQ1 should take 12's or R42's...wtf? the numbering system on the rapid-fires is odd. im not sure what the diff between the 6's and the 12's is. anyone know?

[DOHCRagtopguy]

The temp difference is miniscule between 8's and 6's. That having been said, I ran 8's in my old 3.1 and also in my 3.4.

[joey b]

hmm, i looked on AZ and i saw 6's also. 6's are the same heat range as R44's, which are 1 full step hotter than the coldest you can get (R42's). looked on ACD and the TGP got 8's (same heat range as R42), so the 8's are colder than the 6's. im confused, though, cuz according to ACD, my LQ1 should take 12's or R42's...wtf? the numbering system on the rapid-fires is odd. im not sure what the diff between the 6's and the 12's is. anyone know?

 

Use 12's on the 96/97 engine and 8's on the earlier LQ1. I'm told is has something to do with how far the electrode reaches into the cylinder.

[19Cutlass94]

Its the length of the electrode that deteremines how far the spark travels that deteremines how much it is heated up at determines the heat