I know someone has tried them, either in your DD or olds - do they make a difference?
15 years ago, I tried a plug that was simular on a LG-4 305, but made a few changes, and didn't know what helped, how much.
Just picked-up a brand new [looking] 94 'burban with a 350 [20k on new motor] but a bad trans for a grand, and want to be prepared for 'Bama gas pricing'!!
Hoping for 20+MPG!

 

Never tried the E 3 plugs.

I did purchase a spark plug gapper from Summit to ensure all my gaps were the same.

Simple things can make a big difference.

 

I've never tried E3's either, but saw examples of them on horsepower TV in dyno tests. They seem to like them, as actually picked up a couple HP. I've had Bosch Platinums in my 455 for years when they first came out, and seem pretty good. Not sure what they look like now, but mine have little teeny platinum electrodes, you can barely see.

 

I put a set in my FJ Cruiser a couple years ago after seeing the Horsepower episode. Made no discernable difference. Did not increase my gas mileage either. I still have them in, but all hype IMO.

 

I also have a late model Corvette, and some on the forum there, claim E3's throw engine computer codes on their cars. Not sure what this is all about, just reporting what some people are saying.