[ericrickster]

what have you guys found in power with indexing spark plugs??

looking to try this on an approx 800 hp pump gas 548" bbc

has nothing to do with piston dome clearance,just talking about pointing the plug in a way where the ground strap isn't orientated in the way from the air fuel flow path

also,are you pointing the gap so its facing the intake valve or facing between the intake and exhaust valves,which in my guess isn't all that critical

thanx!

 

[engineguy]

Spark plug indexing is one of those things that, by itself is almost insignificant. But adding up all of those little things can result in somewhat of a power increase . . . .
As long as your piston dome to plug electrode clearance is not an issue, then the plug gap should be pointed towards the intake valve.

 

[67RS/SS]

I agree with Bill, I never noticed a difference when I tried indexing in the past.

Did you make it out to the track yet?

 

[bracketchev1221]

None. I just do it, out of habit to clear the piston domes better.

 

[6t7gto]

How do you index your plugs?
Do you purchase many plugs to get the correct index?
Or do you use the indexing washers to orient the plugs?
david

 

[engineguy]

How do you index your plugs?
Do you purchase many plugs to get the correct index?
Or do you use the indexing washers to orient the plugs?
david

David,

Use the washers.

 

[ericrickster]

thanx for the replies!!

steve,sunday looks like nice weather finally,been rained out for weeks....

 

[6t7gto]

Bill R.,
thanks for the reply.
david

 

[CHITOWNHUSTLER]

There are 2 kinds of indexing washers, flat and cone shaped so check which one's you need.My parts guy has dynoed engines with and without and he say's there is no increase in H.P.