I have a 99 4.6 and getting ready to do some routine maintenance.. want to change the plugs, coil pack, wires.. etc ( I don't know anything about what in it.. its got 134k.. I bought it with 122k last year )... it runs ok.. but here the last little while its been kinda stumbing every so often and power seems to have kinda gone down a little.. I've had some PCV issues and I think I got that worked out... I was sucking oil like it was coolaid.. motorcraft pcv and tube fixed this.. think the plugs may of gotten coated or something. and going off some previous work done on the truck I doubt the plugs are motorcraft.. probably cheapest at the parts store.. the wires are orielly brand and were put on by the dealer when I bought the truck.

question I have .. is would it be worth it to go up to the Davis Unified Coil pack ( not COP ) or MSD/ ACCEL..

Davis claims you can open up the plug and get a better burn and better power.

Plugs im guessing motorcraft on plugs-- but ive heard different styles are better than the other in Motorcraft line up.

I also want to get a tuner -- I've had the Edge before on my 01.. didn't really see much gain ... just harder shifts. im told that other tuners are much better.

Make you recommendations! and post your experiences.
Im all ears!

 

On these engines, anything other than OEM ignition parts is usually a step down, not a step up.

 

The oem systems are as good (hot) as you can get- everything else is just marketing................

 

The Coil packs use a waste system for spark. That means that 2 cylinders are fired at the same time. There is more resistance in a cylinder that has no fuel in it so the other cylinder, the one with the fuel, gets the spark. That being said if there is too much resistance in the wires, caused by a break in the wire or insulation allowing a short the other side will get the spark or it will ark through the plug wire and cause a miss. Start by changing the plugs and wires. Ford OEM is a good choice. Once you have eliminated that then look at coils. Tuners. That is like asking for opinions on ice cream. Check out the
Chips, Tuners & Programming forums. I use Troyer Performance. IMHO the best.

 

Thanks, I have never owned a vehicle with the "coil pack" before.. I read an article awhile back going on about how more reliable the coil packs were over the cop.. and that swapping in an ACCEL unit with motorcraft plugs and wires was a great combo.. however, I know when I had my COP trucks... you didn't even think of running anything other than Motorcraft.. not even the store brand Gold line top shelf products.. I went through a couple on my first ford mod and finally learned my lesson.. just wondering what the real world was on the coil pack. I do know that this truck runs better than any of the other 4 COP fords I've owned.. as in it runs smoother.. not more powerful. I have a DUI dizzy/ coil on my 65 f100 5.0 and it was a noticeably good modification. Wondered if the same would be true with the mod motor. What plug are you guys running exactly? I'll look into troyer. I am researching a 9.75 swap from my 8.8 with 3.55s.. I have a place here where I can get a complete axle for 144 dollars.. with LS. . . . compared to 650 at the parts recyclers around. That should help a bit and compensate for the 34s.

 

I am running Autolite racing plugs. They are 1 step colder than stock. See sig for reason.

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