I've got no idea how you would get an accurate reading on a torque wrench on most of those plugs. I just put them in like any other plug.

 

I think for torque as long as you dont extend the length of the tool like putting a crows foot on the end that would extend the torque wrench an inch or so there is a formula that you can calculate, I don't remember it. but if you add and extension like a regular extension to make the socket reach then you are okay you should get the correct reading. If I am wrong then every I know of a bunch of new vehicles that were built using the wrong torque of nuts that mattered. Seats, seatbelts, wheels, front end parts you name it.

 

3rd set just went in at just under 89K. The pair I replaced at 34K looked pretty new, however the ones I just pulled out with 55K on them needed to be replaced for a couple reasons.

1) Rust starting to form between insulator and body of plug
2) Threads were all discolored and had some rust.

The gap was around .002 over spec, which didn't seem bad. There is no way I would leave a plug in this engine for 100K after looking at the corrosion on the plugs at only 55K.

 

You are exactly right. Any length of extension does not change the torque. As you said, if you add a crow's foot or any adapter that moves the bolt head out of the center line of the tq wrench, the tq changes. We were always told you can do it without altering the tq much by keeping the tq wrench-adapter/crows foot angle less than 45 degrees.

 

2nd set of platinums , 191,200 .. never had a problem or throwing a code
Changed the original set at 45,000

 

In MN, I wouldn't dare leave a set of plugs in that long. Even plastic rusts here

 

no rain in Texas , they come out at 145,000 .... no problems