Hi, I had a coil go out on my 2002 F150. After seeing how much a set of OEM Motorcraft coils cost, I decided to order the MSD #55128 - Street Fire coils. I know I probably pay for it later. Anyhow, I was wondering if I should install new wires too. They claim to put more juice to the plugs so wasnt sure if I needed to upgrade the wires to utilize any benefits.

I was going to pick up a set of Motorcraft Iridium spark plugs unless someone has a better suggestion. (Besides send the coils back... lol)

Thanks for the help!

 

What engine are you wasting money on? The V-8 engines do not use "wires".

If you're wasting money on over-hyped expensive parts, you're probably just wasting money for no benefit.

Just replace the bad coil, install new boots and springs (with dielectric grease) and install new Motorcraft Platinum plugs. You'll be good for another 50K+ miles other than perhaps another coil failure which could happen anyway with new coils. I just carry a spare in the glovebox, they're only $15 at Rockauto.

 

4.6l... just had trans rebuilt. Ordered flowmaster dual exhaust, have CAI already... plan to put electric fans on it and get custom tuned. Dunno what else I can do without putting heads on it to get more HP out of it. Its my every day truck so everyone telling me to NOT put heads on it or else I be replacing head gasket all the time?

PS. In this situation it wasnt wasting money but saving money (today anyways). $400+ for OEM Motorcraft coils is absurd

 

he was not saying you would be throwing money away. more like putting money where you will not see a difference. you can replace all of your coils but will not get any gains that you will be able to notice.
your exhaust yes you will notice it by the sound, your cai you will notice it by the sound, but replacing your coil packs with expensive red painted coils you will not notice.
electric fans are a good upgrade if you tow alot but other than that not really going to gain you anything they will free up some hp but thats it. it is called parasitic loss from your stock fan. a tune and regear your axle or axles will gain you more seat of the pants feel.
there are no plug wires on the mod motors just coil on plug like said before me replace that one coil and your plugs with some dieelectric grease and you will be good to go

 

Replacing coils that are not bad is what is absurd.

 

"Upgraded" coils on a stock engine is a waste, if it were boosted or higher comp than stock etc... you'd see a difference but if your engine isn't capable of "blowing out" the spark as it is, the only performance gain you may see is from your wallet being lighter. Motorcraft coils are 40 bucks on Rock Auto, OE Denso coils are less than 25. Fix the bad coil and buy a spare, the wives tale/sales scare tactic that "If one went bad the others are sure to follow soon" is BS. I have pulled coils out of old Towncar 4.6's during a tune up that were original from the early 90's that still worked just fine.

 

Denso coil packs on Rock-Auto are the same as Motorcraft with an additional sticker and half the price.

More Information for DENSO 6736000

 

Don't overlook the fact that the coils do go out over time due to heat. I went with a full set of msd blaster from Summit...$175. , and yes there is a noticeable advantage , cleaner burn, an slightly better performance and efficiency than stock coils. These have 80 winds vs 60 winds on stock coils . Also went with NGK plugs....Never ran better!

 

your engine might very well be running better but you have to take in to effect one that not all engines wear the same not all parts are put through the same abuse every owner is different.
for example when i changed my plugs i could not really notice any difference with just the truck running but while driving it was like another engine it made a huge difference. same for when i replaced my fuel filter only really noticed the difference while driving.
you could have had a coil pack or two that was losing some spark from age and mileage but they were not bad enough that you could tell at that point from a check engine light. but when you replaced all 8 at once it made a difference.

 

Zoodad, Gotts mod, and GEARS!! No bolt ons will be noticeable powerwise as much as a gearing.

 

This is why most people dont bother posting on these forums. There is always some jackass who thinks everyone knows how to build motors and are master mechanics. Then if someone like me comes along with a simple question... it turns into a "boy, are you just stupid or did your mama make you that way attitude".

As far as changing all the coils in your truck... what the hell is the point in buying 1 coil at a time to replace the 1 causing the misfire? I had a friend who ended up replacing 4 coils this way. So, seeing as my truck is 15yrs old... i decided to purchase a set and do them all at the same time. 7 werent bad but they were 15yrs old and 1 went out so now if any of my new coils go bad and are not covered by the warranty, i have 7 spares. You can call it absurd or stupid if you like... i call it not being a cheap *** sob and doing it right. If you dont agree, dont leave your negative comments. You are probably a back yard mechanic yourself and far from anyone needing to be giving advice on here. Specially if you are just going to be a smartass.

As for the dual exhaust and cai... it wasnt much but i can DEFINITELY feel a difference 100%. Sounds better and seems stronger at higher rpms. Im sure heads and a tune will help my little 4.6 motor, move a little quicker instead feeling lot a boat everytime i pull out in front of someone. Thanks for all the input from those that shared their opinions. Im gonna see what it will do on the dyno after I get heads and custom tune at PHP in Pendergrass, Ga. Will post the results so those considering a few bolt ons will have an idea what kinda HP you gain.

 

Now this i can concur with... it doesnt much matter how mant horses you throw at the wheels if they dont have the gears to make em go fast.

I would do a rear end swap but i do pull my 16ft tandem axel trailer occassionally. Im not trying to build a dragster truck or even something that belongs at the track. I have the supercrew and its a hell of a lot of truck for a small 4.6 motor. Of course i would love to have it geared like a cobra mustang but its a pickup truck so im just looking for a little more umph (power) from a dead start through the lower gears. I can careless about going 150mph.

PS. But for ****z and gigglez what would be a good rearend to make this truck a little quicker?

 

no one can say that a certain gear is going to give your truck the power to launch like a sled pulling truck. it all depends on your tire size that will help to pick out the gears you need to help get your truck that off the line jump.
for example my f250 has the 5.4 with 4.10s and a limited slip diff in the rear and for being a f250 it has a jump to it on starts but once i hit the freeway it takes more rpm to stay at 75mph than it would if i was running lets say a 3.73 ratio which would help my gas mileage but i would loose my off the line jump as it were.
you have to weigh the pros and cons of regearing your axle if you do not take the freeway much and you have stock size tires than a 4.10 would more than likely work in that case. but lets say you have a 35in tire and you have stock 3.73 gears and you went with 4.10s you would gain some power on the low end but that would be about it. with a 35 you are looking at a 4.56 or a 4.88 gear ratio to get you close to the stock power band. if you were at a 35in tire and wanted the effects of 4.10 gears with those tires then you would be looking at a 5.13 or something ratio to net you the low end power you are looking for but at that point you are looking at needing to get alot of new parts more than likely a new case for the ring gear and of course new bearings and the such.
to my knowledge there is not much you can swap axle wise into your truck. you will have to regear.
you can fit all day engine verse gear ratio 4.10s in my truck at 75mph is about 2850 rpm ok so i want more power so now im going to beef up my engine to make that 2850 easier on the engine so now im out about lets say 3k in making my 5.4 more powerful around town it would be a beast on the start and pull like a boss till i hit about 75mph then my gear ratio is going to be to steep and now my motor is going to sound like im running at 95mph. yes the engine is not going to be working as hard to turn 2850 rpm but now my gas mileage is worse than it was before next option is to re gear and so on.
what i am trying to get at is you need a goal. what are you trying to do? are you looking at a truck that has some speed and power or a truck that can pull a 16ft trailer with no problems or a mild street truck that can keep up with a 5.0 mustang.
when you start doing things like heads and cams and tunes there is more that is going to follow with that like how is the bottom end going to handle that extra hp that you added from top end engine work? how long is your trans going to last with that extra hp? what about headers? what about the exhaust system you just did that might have to be changed to let the engine exhale better to help maximize your hp and torque lets say you have 2.5in exhaust system after all your work now you are looking at lets say a 3in system. look at your torque converter it has limits so now you have added power but the truck is not shifting right or the converter is not locking up now you need a new higher stall converter.
you can do what you want to your engine and send back dyno numbers all day but untill you address the other parts of the drive train and exhaust those numbers will not be accurate. you can not half build a engine and expect it to perform in the long term like it did the day you brought it back from the shop.
im not telling you what to do or how do it. in the end it is your truck and your money do with it what you will. i am just trying to inform you that there is more that is going on than just some heads and a tune

 

A gear swap will be more noticeable when towing, around town, and when you do a WOT run while trying to merge into a highway. My wife's Excursion (look at six) had a noticeable power increase when I swapped to 4.30 more than the custom tunes from 5-start, and the SPD Y pipe.