I bought these high compression plugs for about 10 bucks because that's what the heads and overall collection of parts require per HD. i don't want to pay the $20 retail for these on the next go round so i'm looking for and up to date cross reference table . i found the attached but. the models don't seem to line up with the current last few rounds of hd models.anyone have a link?



32186-10/(now)31600105

 

Never heard of a High Compression spark plug. Care to elaborate on the difference compared to regular spark plugs?

 

The heat range is different is all.
Not necessarily needed. I have used stock plugs for everything from bone stock 88's to 165HP 117 engines with out any issues.
I dont know the exact heat range of the plug listed but the Vrod plug will also work.
Also look at NGK DCPR8EIX. That one heat range off of stock and also iridium.

 

Thank you i will look at those as well

 

I don't want to hack your thread but you seem to have knowledge of the H-D plugs.
I have purchased the 3160105 you mentioned for my 117 ci in LRS and also the 31600106, (std heat range). Any idea why the 31600105 has a stamping of 31600104 on the shell casing and the 31600106 has 31600103?
Also the color is not gold, although the porcelain insulator does have the Screamin' Eagle on it.

 

I would make sure you need to run colder plugs before sticking them in. When pulling your old plugs inspect the electrode to see if the heat mark goes over half way. Also inspect the strap for the timing mark. Ideal timing mark should be centered on the 90 degree bend. If it is past the 90 than some timing should be pulled out.

 

Run the regular heat range,you dont need to go with different plugs until your running way too much compression for a street motor.we ran colder,race plugs in our P/G bikes,but we were also running 18.0-1

 

That's some good info. Never knew that.