Dina,

Hotrodders have been indexing plugs for years....you can pick up a few horsepower if done correctly, No BS.
We are talking <10Hp in all likelyhood. If you are trying to maximize what you have and you have the patience (lots of patience) to do it, go for it.

I would suggest that if you are going to do it, plan ahead and take the valve covers off for some paint or powdercoating as getting to the plugs is a lot easier this way.


Cheers,
KrzyFast