I have a 99' F-150 4.2 and was wondering what type of sparkplugs and wires I should put on it for maximum performance. I have had it since early 1999 and have never changed the plugs or wires. Does anyone have any suggestions on what would be the best?
Appreciate any response.

 

Id take a look at some Bosch platinums. Stay away from splitfires they have a tendancy to foul up. Bosch has good wires too.

 

It's tough to beat the OE Motorcraft wires. They are correct for your truck in many ways other than just the custom fit lengths (which is nice). I recommend sticking with them.

As for plugs. . .well, the OE Motorcraft plugs are a good plug and are also tough to beat. Denso, though, would be my recommendation for a performance step up. . .although unless you are really pushing the performance envelope, the Motorcraft plugs are more than enough.

Stay as far away from Bosch platinum and splitfire as you can.


Hope this info helps,

---J

 

I AM USING PLATINUM +4 RIGHT NOW AND THE TRUCK SEEMS A LITTLE SLUGGISH THAN BEFORE. ANYONE ELSE USING THESE PLUGS?

 

I agree with wrongdayJ on this one...

If you want MAXIMUM performance from a plug... you will want Motorcraft COPPER plugs. however they will need to be replaced every 25-30k for optimum performance. I recommend AWSF 32C.

The denso's are a awesome plug but you can get a whole set of motorcraft plugs CHEAPER than 1 denso plug. They are a great plug that will last a very long time tho.

 

I agree with what most of the above said. Bosh suck! Motorcraft or Autolite platinum.

 

Is there a life span to plug wires. I always thought if they were not hard or frayed then they should be ok.

 

Very good question.

Plug wires are one of those items that are replaced on an 'as-needed' basis. You should regularly check them for cracks and torn boots, and for resistance. Remove one plug wire and attach one lead of a voltmeter to one terminal of the plug wire, and the other lead to the other terminal. Record the resistance (in Ohms) and the plug wire number (of the cylinder it goes to) on a piece of paper. Do this for all your wires. Then see if any of the numbers are significantly higher or lower than the others. They should all be about the same. . .if not, then it's time to replace them.

Hope this info answered your question.


---J

 

Does Motorcraft or Autolite make ouble platinum sparkplugs? And if so, how long do they last?

 

Yes it did wrongdayJ, thank you.

 

Does anyone know of any coil pack upgrades as well? Is there anything on the market that will add to the performance, mileage and cure our "rough" idle? I 've seen adds for the Jacobs systems, but it doesn't look like a multiple coilpack system.
Thanks!

 

Any comments on Magnecor wires?

http://www.magnecor.com/

 

I've had great luck in my 87 Bronco (302 motor) with the NGK v groove plugs. They seem to last very well. Has anybody tried the NGK's in the 4.2? I'm at 24K miles, so it's time to do the plugs. Anybody know how much the motorsport wires cost?

Thanks,

Mitch

 

Do the plugs in the 4.2 come out easly. Are they hard to get to. About how much time should i give myself for the change.

 

I bet any newbie that can turn a wrench can do this in one hour or less... I do it in about 20 minutes.