Quick question - installing Denso IK16's and the gap is preset at .044 vs the .039 that the manual suggests. The Denso website says changing the gap is not suggested and they are already set for optimum performance. Has anyone gapped these plugs (carefully) or does the difference matter?

Thanks in advance!

 

Depends on what manual you are looking at. Most plug manufacturers pre-gap their plugs to optimize the best possible spark arc. Unless you are running nitrous or high boost this minute gap difference does not matter.

 

I always check the gap before I install a plug.
You don't know if the guy @ the store dropped it.

 

Thanks for the replies. I checked the gap and they all seem to be in the .041 range so I will go ahead and install.

I really do appreciate the responses!