Thread: Autolite 104's

I have my scheduled tune on the 21st. I have everything besides my plugs. So I went looking around where I live and none of these stores carry any spark plugs besides stock heat range.

This really got me upset, so I instantly went online and ordered six of them. I think I might have grabbed a heat range too cold.

How much would 104's affect my car from 605's?

And what gap should I gap them at?

Mods will be: SD Headers, 3.4 MPS, shift kit, no cat, 180 Tstat, intake.

I would've stayed at 605s. 104s if you start to have knock issues.

How differently will 104's affect my tune from 605's?

Nothing really unless you have knock with the 605s, then step down to 104s.

Originally Posted by Sandman

Nothing really unless you have knock with the 605s, then step down to 104s.

Oki doki, kind of relieved to hear that it wont destroy anything lol

And actually 605s are a step cooler than stock.606 are stock.

The 104s would be good to have on hand though just in case.

What should I gap mine at?

Stock, .060 right? They come pregapped so leave them alone.

For a 3.4" pulley setup. I need to gap them and have them ready.

I've only messed with gap once when I got blowout. I still check them though but have never had to change them.

So I should gap my plugs at .055 for a 3.4 pulley setup?

So I got my 104s in the mail today, and I am going to drop off my car to get tuned tomorrow morning. I need to install my 104's in tonight so the car can be ready. I am still a little unsure on the gap size of the plugs. I was thinking maybe somewhere around .050. Any suggestions for the gap size, it will be for a 3.4" pulley.

.60 is fine.

So 600 thousandths is the proper gap? About 5/8" to be correct?

Seems legit

60 thousandths, not 600 lol. There's a huge difference between .060 and. 600 lol. I'd like to see the ignition system that could run a gap that big.