What spark plug do you recommend?

[Jimbo Billy Bob]

It's time to change the plugs and am wondering what you in Mopar land think is the best. I have a 440 with a lopey cam, 10:1 or so compression, stock but ported cast heads, 6 pack, stock exhaust manifolds and the basic add-ons. I'm not the most knowledgeable on the brands and the "hotness" of the plugs so any recommendations will be helpful.

 

[MarPar]

what gap does everybody run also...(stock intake for me :grin

 

[Jimbo Billy Bob]

I am also running a MSD 6AL ignition box. How bout you MARPAR?

 

[MarPar]

Stock ign. Jimbo, orange box ecu, stock dist.

 

[mr.belvedere]

NGK R5670-6, or NGK XR5's

 

[63RedFury]

Mother Mopar used Champions so that is good enough for me.I have used them in every Mopar I have ever owned from slant 6's to 440's,with and without stock ignition.I have never had any issues with Champions always work great.Gap .035

 

[Jimbo Billy Bob]

What does everybody think about the E3 spark plugs???

 

[scotts74birds]

I dont think much of them, or any other top $ spark plug. The Big 3, and the others, spend Gazillions on dyno, mileage, horsepower, torque, emissions, and longevity testing. If there was a "Silver Bullet" out there, they would be using it! My opinion is that ANY difference in plugs, or wires for that fact, can only be found on the dyno.
I'll buy an aftermarket set of wires, but my criteria is heat resistance due to the headers. If you arent Pro-Street, or something like it, you dont need the mega-bux wires.
JMHO.

 

[Meep-Meep]

I figure the factory plugs are called out for engines with 9-10:1 CR so that's good enough for me. No reason to run super cold plugs unless you have a bunch of compression and are running max RPM for extended periods of time. I'd say the hottest plug you can run without melting down the engine is about right.

 

[65-440]

Autolite 64's

 

[scotts74birds]

I dont want to hijack, but I feel this is close enough to deserve a mention. Anyone "index" their plugs? Would this make more of a difference than the plug itself?

 

[Meep-Meep]

I dont want to hijack, but I feel this is close enough to deserve a mention. Anyone "index" their plugs? Would this make more of a difference than the plug itself?

I tried that once but I didn't notice anything. As I understand it if you stack washers to adjust the angle of the dangle it affects how the plugs cool so it's not recommended. Side gaping is probably a better bet if you want to expose the electrode.

 

[Meep-Meep]

To comment on gap clearance. The higher the compression the smaller the gap should be because high CR tends to blow the spark out. On my 71 Ranchero (low CR Cleveland) I run .045" with an MSD.

 

[scotts74birds]

Supposedly, the copper indexing washers are thin as ****. So the "worst-case" of backing-out a plug would only be ALMOST one whole thread. In all honesty, most of us probably over-torque our plugs anyway!! LOL

 

[69 Runner]

Champion J-11Y in a big block

 

[YY1]

I second the Autolite reccomendation. They always worked better than Champions for me, and wern't as easy to foul.

 

[65-440]

I second the Autolite reccomendation. They always worked better than Champions for me, and wern't as easy to foul.

wow, someone agrees with me on autolites !! for some reason they do seem to work better than champions.

 

[Meep-Meep]

Supposedly, the copper indexing washers are thin as ****. So the "worst-case" of backing-out a plug would only be ALMOST one whole thread. In all honesty, most of us probably over-torque our plugs anyway!! LOL

That's a good point! Indexing may not make a hill of beans worth of difference but it doesn't take much to find out.

 

[Meep-Meep]

wow, someone agrees with me on autolites !! for some reason they do seem to work better than champions.

Now that I think about it I used to run nothing but Autolite 74's in my MoPars and had great results.

 

[Dennis H]

Ngk