Whats with the autolite 3923's? I noticed that almost everybody runs them.

 

They are one or two heat ranges colder than the stock reccomended spark plug is. This will lower your combustion chamber temperatures and as we all know a cool motor is a happy motor. It will also help with pinging if you have that problem.

 

I just realized that as I was scrolling part numbers here at work. I was thinking about going 1 step hotter, but I don't know which champion # that is. I guess I'll look it up before I go home.

 

I could be wrong about this but I doubt you will see much improvement with a hotter plug. Really unless you have major mods to your motor your spark plug isn't goint to make that much difference anyway. The big thing with the 3923's is keeping the pinging to a minimum. Really you should go with a set of standard heat range Champion truck plugs. I had the best performance and mileage in my truck with those, I have just been too lazy to swap them back in.

 

That's what I've got now. I run 89 octane with 10% ethanol and in the mornings it starts a little rough and acts like it's not burning all the fuel even after it warms up so I thought I'd go 1 hotter to see if it burns better.

 

Personally I hate ethanol fuels. My truck seems to perform worse when I use the 10% that they sell around here. That said I'm still of the opinion that changing your spark plugs isn't going to fix that problem, unless they are really overdue for a change. You might look into an ignition upgrade. There is a write up in the DIY section here that shows you what to use. I have the same set-up and I thought it smoothed the idle out, I've never analyzed my exhaust to see if I am running rich or anything though. Anyways I'm not discouraging you from trying a hotter plug, trucks are different and maybe that will work for you. If you decide to give it a shot let us know how it works out for you.

 

I'm just guessing cuz it was bad when I had ngk's in it. Then I changed back to stock champions and it got better, but it's still not great.

 

So you have standard champions in your truck right now?

 

Yep. the rc12yc's.

 

Ok I was suggesting that you run the correct heat range of the Champion Truck Plugs. They have a bigger electrode than the standard champions. I have had the autolites, the standard champions and the truck plugs and I flet like I got the most performance and the best mileage from them. Give me a second and I will run out to the garage and get the number off of the box for you.