Sidegapping Plugs
Posting Guru
Joined: Dec 2000
Posts: 1,686
Likes: 1
From: Racine WI
Sidegapping Plugs
Will sidegapping my spark plugs in my slightly built 390 help it quite a bit, if so what should i expect ? better gas mileage ? smoother idle ? more power , anyone with info or who has done this please let me know here as i would like to know the effects i can expect
Senior User
Joined: Jun 2000
Posts: 350
Likes: 0
From: Calgary Canada
Sidegapping Plugs
This link was posted a while back in the General Conversation forum. http://performanceunlimited.com/illustrations/sparkplugs.html
" Someone put this together, I must be able to take it apart! "
Dustin
" Someone put this together, I must be able to take it apart! "
Dustin
Post Fiend
Joined: Sep 2000
Posts: 8,238
Likes: 3
From: Oregon
Sidegapping Plugs
This is a new one on me, nice link, thanks. Otto, let us know what you think if you do this mod. If its really what its cracked up to be (more power, torque, & mileage) with a such a simple mod I don't know why they aren't manufactured this way. Makes me wonder if this is a urban racing myth. I wish somebody had dyno figures. Anyways, keep us posted.
If your knuckles ain't bleeding you did something wrong.
'72 F-250 "Hi-Boy" 4x4, Dana 60/HD44, FE390 @ 400hp(purt near!), 4-speed, custom suspension w 4" lift, mud on black.
If your knuckles ain't bleeding you did something wrong.
'72 F-250 "Hi-Boy" 4x4, Dana 60/HD44, FE390 @ 400hp(purt near!), 4-speed, custom suspension w 4" lift, mud on black.
Elder User
Joined: Jun 1999
Posts: 861
Likes: 0
From: SE PA
Sidegapping Plugs
No dyno runs to back this up, but, I think it has made a difference in my 460. Just follow the instructions in the link and index them with relation to the piston/cylinder, seems to me it won't do much good if the electrode is covering the open side were you have the most exposure to the mixture. Index them to face into the combustion chamber with the gap, to expose the most spark to the mixture. They do make washers for this and really is not that hard to do. Hardest part was figuring which direction to point them, used a penlight to look into the cylinder and then decided which direction it would do the most good. Do realize that it will require plug changes more often as it tends to side-burn the center of the plug. Change mine every 6-8k miles and use only copper plugs.
