Sorry big Jim I know more than you think Im a mechanic im working on my ASE certification. Gap does have something to do with it. If you knew about the +2 and the +4 you cant a just the gap. A gap can make the spark hotter which gives more hp and bad gas milage. Most people use the factory gaps because of the milage and the stock performance. When your running a high performace application you can ajust the gap for hotter spark. Most stock cars can not handle the hotter spark. The bosch +2 and +4 is designed for a hotter spark with the extra electrodes and the gap set.

 

Like I said, you need to read more and get a grip on what is happening and why it is that way... Your post is incorrect in all respects! You have no idea what is going on in there... Read those books and try to understand why the gap is wider and why the heat range is different... You do not understand this yet or you would not use the "hotter" term.
Big Jim

 

When a gap is wider it take more voltage to make a spark due to the size of the gap. It is harder to spark between the gap when its too wide which in return gives you crappy gas milage and performance. When the gap is shorter than stock it takes less voltage to create a spark due to the size of the gap. When the gap of the plug is short the spark is hotter. If you look at a bosch platinum + series plug the gap is way shorter than stock.

 

I have used Bosch plugs for the past 175,000 miles on my '94 2.3L and you know...they have always worked wonderfully! I have tried other plugs including Motorcraft, and they have done nothing but Lower my MPG. Big Jim can type all day long that Brand has NO effect on performance, but I won't buy that for a moment. He did pose the the question, why do you think Ford uses these [Motorcraft] plugs? Well Big Jim it sounds like you need to take time and realize that this world [the real one] is not based on how electricity flows through "the gap" or how much someone does/or doesn't know, it is ALL about money. Ford manufactures their own plugs becuase it is more feesable for them to do so, Bosch...Autolite...Champion...AC Delco...and all the rest are there for COMPETITION...if you don't understand how important competition is to the automotive industry why don't you look into France's Automobile Industry...France charges outlandinsh tarriffs (taxes for those who don't know) on imported (ford, chevy, dodge, kia, ....) cars, which means that only French cars can be afforded my 99% of the French people...and all the cars are junk...(when is the last time you saw a French car in the US?). Bosch may work in some motors fine, others not so fine...So be it. If you honestly believe that there is no difference between brands, that is your opinion...and you are entitled to that...but I am entitled to mine.

There are differences between brands, maybe the heat ranges are identical, maybe the sparks are the same...but are the materials that it is made of the same? Could Bosch plugs be made of a better quality of platinum then Motorcraft (or vise versa)? If one plug has a lower quality material, would the spark "jump" as easily as the others? Since the voltages and "timings" are the same, wouldn't quality of materials have an impact on the ability of air/fuel mixture to ignite?

It sounds like someone in this forum needs to be a little more open-minded and understanding. There are definate differences in various parts in the automotive industry...if there wasn't differences there wouldn't be competition...therefore substandard/unimproved parts from ALL Auto Manufactures [Ford, Chevy, Kia, Toyota...]

 

Night me that is a great point. That basicly ford puts the motorcraft in because it is available to them and its is at a low cost to them. That make pretty good scence to me. Thanks for bringing that up. I never thought of factory parts that way.

 

Ford (as like the rest of Dealers) want your money. There is NOTHING wrong with Motorcraft parts, I am sure that they are more model specific than say Bosch or Fram or whoever. The point is, you can't assume that Motorcraft is "absolute" best for the vehicle (or in its use). Ford wants to support their automobiles and to please their customers, and that's okay! But they will *usually* charge extra for their "premium" part/service then others...but the competiton is what keeps the price of these services just shy of insane! And competition is what causes these parts/services to increase in quality and reliability (generally speaking)...

Back to the point...Bosch or Motorcraft? For me Bosch works well in my '94 2.3L...they work well in the wife's '92 Geo Prizm...they work well in my mother's '92 E-150 (w/ 302)...personal preference and trial and error!!!

 

Guys it is not about brand! It is about why the gap has been widened. It is about why some plugs have more than one ground for the electrode. It is about why a more powerful coil... All of these things add up to a spark in (hopefully) a flamable mixture under compression. You either read and understood the books or you simply buy the "hotter" stuff because it sez that on the wrapper.. If you think the SPARK from one plug with a 45 gap will make the mixture burn better,faster, or more powerful...then you need to go back to 101 and reread and think the answer all the way thru.. yeah the only difference in plugs that actually ARE the same heat range is that some materials will outlast others... each being new they are all the same!
Big JIm

 

Each being new, they are all differant. Hopefully you will realize I said absolutely nothing about gap, and I did that completely on purpose...

 

My point about gap is that before a guy can make an informed purchase and change brands of spark plugs from original, he MUST investigate WHY is he changing and WHAT will the results of that change be? Without KNOWING what a spark plug DOES and WHY it does it and under what circumstances it WILL DO it... then the custoner might just as well get the PINK ones because they are the prettiest!!!
Doncha get it? If you change brands then you should have a reason other than color of the BOX or the words in the TV commercial...
So I'm trying to get folks to investigate what exactly it is a spark plug does and why have they (spark plugs) changed over the years and that includes the GAP!
And yes if you break the heat range down to bare numbers, the factory plugs are in the factory specified heat range and all others are CLOSE to that range.. It all boiles down to they will ALL lite up the mixture but which one does it correctly? And WHY?
Big Jim

 

Bosch makes some crappy plugs, I really don't know about their wires, but if the plugs are as bad as they are the wires are not a good bet either. I only had about 3,000 miles on my bosch platinum plugs and one of the plugs carboned up on me I couldn't believe it, heck it caused my truck to not start after the first intial startup of the day, so I figured I would replaced the plugs back to autolites and low and behold the plug was definitely the culprit of my situation with my truck not starting reliably. I will never use anything bosch except maybe an o2 sensor they make good o2 sensors lol...

 

Not meaning to upset the applecart, but Motorcraft plugs are made by Autolite. They do have to make them to Ford's specs. They are quite specific right down to the number of threads, to the percentage of platinum. The main reason plugs have platinum tips is because it is a better conductor of electricity. This, plus the higher ignition voltage allows for a wider gap = hotter more robust spark. Does anyone remember when we had to change plugs every 12,000 miles? Between the lead in the gas, and the steel plugs, you were lucky to get that far. Anyway, the way I feel is use what works good for you. I was ASE certified too, but that was back in the stone age. The auto industry is constantly changing. It's a PIA trying to keep up. It's fun though.

 

Well, I don't mean to upset your applecart, but you are wrong on two points:

1) Motorcraft and Autolite spark plugs are both made by Honeywell, a division of Allied Signal Corp. They are built to different quality standards!

2) Platinum is used for the electrodes because of it's resistance to erosion. Copper actually has a lower resistivity than platinum, but erodes faster and will never make it for 100K miles. One thing to keep in mind, the higher resistivity of platinum is in the range of 1 OHM, and DOES NOT effect performance like some people think!!

One other fact, Ford's EDIS fire 2 plugs together in series, and each plug gets opposite polarity spark. The result: the center electrode will erode on one plug, while the outer electrode will erode on the 2nd plug.