indexing spark plugs

[techsan23]

Saw an old episode of horsepower tv this weekend, and they were indexing the plugs on an engine (aiming the plug gap between the intake and exhaust valves). They claimed that in most cases the engine will idle better. I saw a set of indexing washers at a local auto parts store for $18. I am curious if anyone has tried this and if it made any difference.

[transamtom1]

Re: indexing spark plugs

You might get 1- 2HP if your lucky,personally I don't think its worth the time and effort.

But if you have the time and nothing better to do what the heck go for it.

[dafirebird]

Re: indexing spark plugs

I wouldn't waste the time on a street car (daily driver). Indexing the plugs would be important for a race car where everything is multiplied, e.g., half psi difference in tire pressure during a race changes everything, not for driving to work.