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Desided to change spark plugs now have surging

1062 Views 8 Replies 5 Participants Last post by  shakerhood
I changed to Autolite 25's copper I hear they are an excelent in the foxes. Well I had Bosh platnum 2s in there before. I don't know about 2s but I heard platnum 4s suck. Well anyway I put autolite 25s in and it now runs like crap.

(I just want to know why it runs good with platnum 2s and not autolite 25s which I would thing would be the perfered ones.)

Should I try getting the bugs out or just put platnum 2s in?
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It happens at idle.
I set the gap at .044 just like the tech manual says.
For some reason for 91 and up it says .054 I guess they have a different cam I know 93s have different pistons.

Mine is 89 an following the directions it said gap a .044
Well it might be that it wants a hotter plug I don't know my car is very touchy and it doesn't take much to make her act up if she doesn't like something. So I put the Bosch plat 2s back in. Runs like a champ now most people hate platnum in 5.0s but mine seems to like plat 2s so that's what she'll get.

I am running a slight timing advance but still burning reg oct 87. Oh and I beat down a 97 Z28 today he had 22's on it lol all show no go.
I don't know I used a Chilton's Manual it might have had a typo. Either way problem solved Thanks I will diffently look that up for future reference at Ford or somewhere because I don't have the original owner's manual or hood.
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