Which NGK Spark Plug Do You Use In Your 440 on the Street?

[MCODECUDA]

Which NGK Spark Plug Do You Use In Your 440 on the Street?

 

[turbine68rt]

Stock #7189 XR4IX

 

[Aron Gleason]

Number 6 heat range

 

[MCODECUDA]

Thanks, the speed shop gave me R5670-8’s and I’ll exchange them for R5670-6’s.

 

[RJRENTON]

Which NGK Spark Plug Do You Use In Your 440 on the Street?

I guess it depends on which cylinder heads you are using....the 906 iron heads use a 3/8" reach plug and if you are using an aftermarket aluminum head design, which usually use (but it depends on the manufacturer) a 3/4" reach plug. For my RS23VOA****** GTX with 906 heads l use a Champion UJ-11G pladium alloy electrode or Champion HO-8A platinum alloy center electrode...both plug use a non projected nose design. But the final determination is based on ignition advance characteristics, compression ratio, cam profile and fuel mixture and delivery system. Just my opinion of course.
BOB RENTON

 

[Hemirunner]

Thanks, the speed shop gave me R5670-8’s and I’ll exchange them for R5670-6’s.

What’s the combo and fuel?

 

[beanhead]

If those are what the shop gave you I'm assuming you have factory iron heads.
Is the engine modified, and if so how much?
Stock heat range would be NGK 4 with 5 being one step colder.
Tell us about your combo and usage and then what I like to do is run two heat ranges I think are 'close' and then watch them to see how they color the threads/strap and than make my final determination. It takes a little effort with modified stuff..

 

[beanhead]

What’s the combo and fuel?

Beat me by a half second! Must be the turbo lol.

 

[Hemirunner]

Beat me by a half second! Must be the turbo lol.

Lol, I’ve been hitting the practice tree!

 

[theman440]

What cylinder head and compression ratio?

 

[moparedtn]

Champion J11Y/Mopar 34P. As they came with....

 

[MCODECUDA]

I’m running a pretty much stock motor with 906 heads. The car didn’t come with much information and what info it came with wasn’t correct.

 

[beanhead]

I’m running a pretty much stock motor with 906 heads. The car didn’t come with much information and what info it came with wasn’t correct.

In that case I'd start with a mix of 5 and 6 heat range plugs. Keep an eye on them for a bit and go with what looks the best, no fouling or signs of overheating. If they both check out okay after the first few drives I'd run them for maybe 100 miles and use the heat range that looks cleanest. Then if you really want to get OCD with it you can mix the winner with the next closest range and repeat the test....but 5s will probably be fine for your engine.

 

[khryslerkid]

To answer your question about NGK I use the NGK 3332, roughly equivalent to J11Y and J12Y and is the correct plug for a stock 67 440.

Edit: XR5 3332

 

[beanhead]

To answer your question about NGK I use the NGK 3332, roughly equivalent to J11Y and J12Y and is the correct plug for a stock 67 440.

...which is a 5 heat range plug.

 

[khryslerkid]

The XR5 3332 is the "5" heat range. Should have added the XR5 in my previous post.

 

[MCODECUDA]

Now that I think about it 3332’s are what I ran in another 440 that I built.

Thanks

 

[Master Gunner]

NGK R5670-6, stock #2746. Static comp 10.3, dynamic comp 8.6, Keith Black step top pistons with 906 heads. Plugs are a nice chocolate brown.

Mark

 

[furious70]

XR7 but turbo charged