I'm trying to do things more professionally these days so I routinely go to my handy torque specification sheet that I downloaded from the web for an Olds 455.
It wants me to torque my spark plugs to 30 ft.lb. This seems like way too much. I've got a 71 455 with iron heads.
I'm ready to put them in by feel like I always have but I'm sure I've never tightened them to 30 ft.lb. Is this accurate?

 

Sounds about right. Remember you want them to seal the cylinder properly as well as not fall out of the hole.

 

My 66 425 says 25 ft lbs. I was uncomfortable the first time I used a torque wrench on it, suddenly realizing that I had under torqued them forever.

 

What the heck, try indexing the plug...

 

I first heard about indexing on Musclecar Garage. Should be easy enough to do on a wide open 350, 425 or 455. Any idea how you would do it on a V6 when you can't see the back spark plugs? Hmmm, ok I just remembered, you use a mirror tool, but it's a real PITA to work on the back plugs of my 3800. You have to take off a bracket just to get to one of the plugs. Don't forget that if you're indexing, you need copper washers to crush or the plugs won't seat and seal right.