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Discussion Starter #1
Just got off the phone with Autolite, had some questions about Plug Temps and Nitrous.

First off, heres the info I have:
764s / Stock
103s / 1 heat range cooler
AR94 / 2 heat range cooler
AR93 / 3 heat range cooler
AR92 / 4 heat range cooler

Right now im running 764s, they Suggested AR93's with a Stock Plug Gap for a NX Wet 75 Shot.

Everyone has said to shorten the gap, and only 1 stage cooler plug is good enough for a 75 shot? So Now What?!?!

***Cliff Notes
For 75hp NX Wet Shot:
What I Thought: 1 step cooler plug, With Smaller Gap
What I was just told: 3 Steps Colder, Stock Gap

What to do!>?!>!
 

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I know people who run 75-125 with 764's at a 35 gap. where did you here that. The problem is as you go down colder you car will run like ass N/A. you have to have a happy medium unless you want to constantly want to change plugs everytime you want to race. I gained nearly 15 hp by going back to stock plugs. there are people that use stock plugs for 50-75 shots
 

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Discussion Starter #3
Well, a 35 gap is smaller than stock, I think stock is in the 50 range. Id definately be glad with a Happy medium, I dont want to have to change the plugs all the time, thats a major P.I.T.A.

I have the 764s in right now, I think they are gapped at about .052, and I tested a 50 shot with that and was fine. Do you think for the 75 shot I should Keep the 764s and close the gap a little bit? Or maybe go with a little colder plug i.e. the AR94s and put the gap around .040... Id rather foul a plug, than replace a head.
 

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Discussion Starter #5
Danger Dude said:
I would run the 764's and lower the gap to 35. you are not running enough Nitrous to require a colder plug than a 764
Thats what im thinking.
Granted, the 764s arent colder than stock, the only diff is they are copper, not platinum. Thats the only thing really im worried about
 

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Discussion Starter #7
Danger Dude said:
764 are one heat range colder than 765 the suggested stock replacement plug. All of the autolite base plugs are Copper
You might be half right. This is from the Autolite web site:
99+ GT - 764
99+ V6 - 605
<99 GT - 764
<99 V6 - 765
 

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Discussion Starter #9
Danger Dude said:
I am only talking about V6's
Well yeah, thats all I really care about too. Im just confused. You said 764 is colder than 765, that might be true, but why is 764 stock on a GT? Does the GT need colder plugs?

If thats the case, Id assume the difference between 764 and 765 is the same as the difference for the 764 and 605 on the 99+, correct?
 

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Discussion Starter #11
Danger Dude said:
I cannot be for sure all I know is there are alot of 99+ cars running 764 plugs
True true, those seem to be the majority.

I havent heard of anyone else saying to go with 2/3 step colder plugs, so its cant be a bad plug.

I think ill just pull em, check em out since ive used a 50 shot, then re-gap em at 35, and see how the 75shot acts.
 

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Going anything over autolite 764's is a waste when running 75-100 shot.
Just run the 764's with a .040 gap on the 75 shot or a .035 gap on the 100 shot.

The colder plugs you run the less performance you get NA and "may" get cold start problems.

Zach
 

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v6stanger said:
The colder plugs you run the less performance you get NA and "may" get cold start problems.
???

Colder plugs refer to how hot the tip of the plug stays. You need to tip of the plug to stay a certain temperature to keep carbon from forming, but not so hot as to glow red and cause preignition.

As long as your plugs aren't carboning up or causing preignition they aren't too cold, or too hot. Nor will they hurt performance or cause cold start issues.

Steve
 
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