Old Plugs

[jaywish]

Excuse the brain slip, I use motorcraft not autolite.

Jay

[Lincolnmania]

autolites used to be good, havent used them since they are made in china, i had a few sets with at least one dead plug so stopped using them.......i only use motorcraft copper now on 5.0's

change the pcv screen, no amount of cleaning will help them, hint, use a 4" drywall screw to remove the old one.

[turbo2256b]

There is one other thing asuming all else is good. That side of the engine has a water connection to the EGR spacer (to cool the EGR valve). Often I have seen plugs 7 and 8 to be a bit different than the rest. Long ago in the carb days I learned that manifolds with a rear crossover adding a bleeder line from the rear crossover to the front crossover made jetting the carb square. By square back then it was common to stager jet a carb to achieve proper plug coloring.
Square jetting might be like 68 right front 70 left front, and 76 right rear 78 left rear. Manifolds were designed to address this by rotating the the carb flange a bit. Original Torker intakes were one of the first.

Manifolds with a crossover in the rear seemed to require a smaller difference in the staggering between left and right than intakes without a rear crossover. I started to drill and tap manifolds without crossovers in the rear and run lines to the front crossover. It ended the need for stagger jetting plugs looked nore even across the board. Began to do it on other engines becides Fords.

I have also done it to EFI SBFs there is a plug on the opposite side of the EFI lower. I tee the left and right bank togeather and run the line into the EGR spacer. This seemed to help in the same way. Later while working with Intermotive on a project for Ford (a dual runner intake for a 2.3 Ranger I designed was on thier dyno) I saw they were running such lines on some builds. Questioned them about it they had come up with the same conclusions.

[porschpow]

Is this true?? I never knew that

Could be cross fire issue with #7 plug. Did you ever correct for that issue? Platum plugs in older vehicles not always a good idea. The tips burn hotter because of the material and often cause issues.

[sly]

yes, this is true.

Cylinders 7 and 8 fire one after the other so the wires should be separated by at least a full wire width between at all points. (run 6 between them from the dizzy is the usual fix).

[cld783]

Is this true?? I never knew that

platinum plugs in older vehicles? it depends, but most platinum plugs are still copper core anyway.

i've had good luck with the autolite double platinums.

[BigT]

Just came back from an Indiana road trip and so far my Platinum plugs are running good.

[porschpow]

ok so where is cylinder 6, 7, 8???

[cld783]

ok so where is cylinder 6, 7, 8???

1 2 3 4 passenger side

front of vehicle <<<<<<<

5 6 7 8 drivers side