Spark plug radius for + horsepower

Eric94GTvert

Founding Member
May 13, 2002
596
1
16
PA, Nazareth
Wanted to know some opinions on those doing the spark plug radius thing.
For those that don't know, it's grinding down the spark plug electrode until it's a half moon instead of the regular sharp edges. This is supposed to add horsepower somehow.

Anyone have experience with this?
 
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This is incorrect. The spark likes to jump from a corner, the way lightning likes to find sharp edges too... (if you notice it always hits the corner of a building if it does not have a lightning rod) What will help is cutting the electrode back to reveal more of the spark.


OOOOO
O
O__OO__
OOOOOOO
OOOOOOO


OOO <---cut back
O
O__OO__
OOOOOOO
OOOOOOO


So it looks more like the second awesome illustration above, with the electrode now covering approx. 50% of the plug tip. The only real drawback here is shorter plug life. Power gains will probably not even be noticeable to be honest. :bang:


Maybe the rounding thing would work if you keep the bottom edge of the electode nice and sharp... Perhaps this would help to keep the spark centered since it wouldnt be as prone to jump from side to side?
 
Badder Adder said:
OOOOO
O
O__OO__
OOOOOOO
OOOOOOO


OOO <---cut back
O
O__OO__
OOOOOOO
OOOOOOO


So it looks more like the second awesome illustration above, with the electrode now covering approx. 50% of the plug tip. The only real drawback here is shorter plug life. Power gains will probably not even be noticeable to be honest. :bang:

QUOTE]

I agree, that is an awesome illustration :D . I've been searching for a while today just for the hell of it but I can't seem to find the site. (pretty bored here, have a 3 day lay off from work) Anyone have experience with cutting the electrode back?
 
I cut them back when I did the tune up before last. It's hard to say if it made more power or not I think it helped a bit but it could just be in my mind. I didn't do it on my last tune up becuase I didn't have the time to grind them down but when I get time I'm going to take them out and do it.