Halo Plugs

[zpiloto]

I'd did this test about a month ago just forgot about putting it up. I've seen no increase in city mileage -zip- nada even though I don't know how you could possible test it. I tested it to a modified NGK plug which might be as good as the Halo's. I'll just modified the $2.00 NGK again next time and leave it at that.

[ZugyNA]

Originally Posted by zpiloto

I tested it to a modified NGK plug which might be as good as the Halo's. I'll just modified the $2.00 NGK again next time and leave it at that.

These are the ones with the hole drilled in the ground electrode and with the center electrode cupped?

[zpiloto]

Originally Posted by ZugyNA

These are the ones with the hole drilled in the ground electrode and with the center electrode cupped?

Yes