Indexing Spark Plugs--is it worth it?

[z boy mn]

Hello everyone, I've been tuning up my triple webers, and everything is about perfect.

They're synched, the jets are right, they're all a nice even color, and it starts, runs, and drives well.

So, now I'm wondering if it's worth indexing the plugs, too. And, as the valves are so closed together, where should the gap face? My assumption is that the gap should be pointed up so it's exposed to both the intake and exhaust valves, but would it be better if it were angled to the right (2:00) or left (10:00)?

Curious!

[John Coffey]

You will not notice a difference through the seat of your pants. If you want to do it face the open part of the gap towards the intake valve.

[z boy mn]

Thanks, John, and just to be sure...the intake one is the one to the right (as you're looking at the spark plug side of the engine).

[Zed Head]

It varies. The easy way to tell is by looking at the manifold intake runner. It points at the valve.

[Carl Beck]

The exception here is - pop-up pistons. If you are running them - you MUST index the plugs. You don't want the piston peaks smashing the spark plug gap closed.

FWIW,

Carl B.

[cygnusx1]

I once tried side gapping an old set of NGK's and it made an appreciative difference in smoothness of idle, and smoothness of revving. I am not sure about the power, but it felt slightly torquier...of course that's completely unscientific.

Save Gas And Incerase Horsepower By Side Gapping Spark Plugs

I was inspired by the four electrode "Golden Lodge" plugs of my past Alfa Romeo.

[z boy mn]

I'll poke around today under the hood and see what I can do. Thanks for all your suggestions! Also, I didn't know there was sometimes called "side gapping," Dave, thanks for the heads up--I did do a search before I posted this and didn't find anything on indexing, but this sounds like the same principle. Has anyone else done this? Looks like a pretty heavy mod to a spark plug....

Also, I noticed at Summit, Jegs, etc., they sell indexing washers. I'm assuming if I use those I'll need to leave the original crush washer that came with the plug on the plug and add the indexing washer in front of that (i.e. closest to the engine). I saw a Youtube video yesterday that said to cut the crush washer off, but that sounded like a bad idea to me. Of course, my plugs have been in and out some 30 times this season (I keep notes), so I'm not sure they have any "crush" left in them.

Oh, and Carl, thanks for the warning on the pop-up piston variety...luckily, mine only pop down! :-)

Edited August 9, 2014 by z boy mn