Spark plug selection?

[Longgone]

How do you go about selecting a spark plug when you`ve gotten so far away from the stock engine? What is a benchmark and what factors govern where you go from there?

 

[66340SEDAN]

I run NGK plugs in my 340 engine, I have always heard those were good. I have never had any problems with them. I am also going to use them in my built 340 engine for my Valiant.

 

[2shelbys]

All the info you will ever need is right here:

http://www.4secondsflat.com/Spark_plug_reading.html

 

[Longgone]

All the info you will ever need is right here:

http://www.4secondsflat.com/Spark_plug_reading.html

Wow there`s a lot there! I`m starting from scratch with heads that have a different plug reach, different cam, timing, comp.ratio, displacement, header, and just about everything else.

 

[321Scamp]

I have heard a few good things on the new spark plugs E3 Diamond Fire. I also heard some down sides to them too. I thought I might try them and report in on them.

E3 Diamond Fire Website

 

[prostr340duster]

Depends also if your running a aftermarket electronics. I run a jacobs box and they recommend stock plugs gapped .015 over. Works great for me and never had a problem.