What's wrong with Bosch +4 Platinum plugs?

[u3b3rg33k]

Not sure if this is true, but when I observed the spark plug outside of the engine, the spark moved around the prongs randomly. Not all 4 prongs received spark at the same time.

Nor will they ever. Having 4 gaps just gives more room for the combustion to spread outward.

[priapism]

It's all hear say. I'm using them on 2 e30s, absolutely no problems at all.


Sent from my HERO200 using Tapatalk

I don't think it's so much about "problems" as it is about how they affect combustion.

[xwill112x]

I don't think it's so much about "problems" as it is about how they affect combustion.

If your engine is healthy how could it affect it? A blue spark is a blue spark, and it all ignites the same.

[dnguyen1963]

I don't think it's so much about "problems" as it is about how they affect combustion.

Well, if it affects the combustion...let's say incomplete combustion...would you not observe hesitation during acceleration? Gasoline is extremely combustible, a single spark will ignite the gas and burn it all. I do not see how it would affect combustion. Truly, I have not seen any difference whatsoever since I switched to +4 four months ago.

[xwill112x]

Well, if it affects the combustion...let's say incomplete combustion...would you not observe hesitation during acceleration? Gasoline is extremely combustible, a single spark will ignite the gas and burn it all. I do not see how it would affect combustion. Truly, I have not seen any difference whatsoever since I switched to +4 four months ago.

But thats not even the case, the fact that it has 4 places to arc from, gives it so much chance to have a better spark than a plug with only 1 prong. Even stock OEM plugs for a m50 is 2 pronged. So how could more chance for a better arc equal up to incomplete combustion?

[dnguyen1963]

but thats not even the case, the fact that it has 4 places to arc from, gives it so much chance to have a better spark than a plug with only 1 prong. Even stock oem plugs for a m50 is 2 pronged. So how could more chance for a better arc equal up to incomplete combustion?

qft.

[u3b3rg33k]

that's what the marketing says, but if you believe everything marketing tells you, you're running pulse-stars.

[xwill112x]

Not marketing, Those are solid facts I have pointed out in this thread. Not something someone told me.

[kamotors]

I had them for 4 years w/ zero issues, only fouled when I turbo-ed the car.

[nando]

But thats not even the case, the fact that it has 4 places to arc from, gives it so much chance to have a better spark than a plug with only 1 prong. Even stock OEM plugs for a m50 is 2 pronged. So how could more chance for a better arc equal up to incomplete combustion?

facepalm

[smooth]

But thats not even the case, the fact that it has 4 places to arc from, gives it so much chance to have a better spark than a plug with only 1 prong. Even stock OEM plugs for a m50 is 2 pronged. So how could more chance for a better arc equal up to incomplete combustion?

the material is different though. platinum has different characteristics than silver or copper so when most people talk about incomplete combustion I believe the concern is more about what it's made from rather than the shape/design of it. Not being able to gap the plugs also concerns some people.

You'll get a lot of interesting commentary, though, if you don't follow conventional wisdom. Apparently even things like pointing out that multi-pronged plugs are non-indexed (they're actually *self* indexing) pass muster to some people because, you know uh, marketing :|

[u3b3rg33k]

But thats not even the case, the fact that it has 4 places to arc from, gives it so much chance to have a better spark than a plug with only 1 prong. Even stock OEM plugs for a m50 is 2 pronged. So how could more chance for a better arc equal up to incomplete combustion?

No. Chance is not related to potential surfaces to arc to. in theory, you could arc from the electrode to the top of the piston - but you won't, electricity takes the shortest, easiest path possible every time. if they're all perfectly spaced from the center, at best the path will be random.

If anything, the benefit of the +4 style might be that if it's perfectly centered in the bore, the flame front can propagate down towards the piston - or is it out towards the walls - or is it yes?

Maybe. Or it can propagate outwards radially more easily.

But what's best? Who really knows? probably the team that designed the engine - if they bothered at all. I'm sure F1 cars have expensive plugs.



some of that engineery stuff:

http://teacher.buet.ac.bd/zahurul/ME401/ME401_combustion_SI.pdf

[0000000000]

formula one cars use these http://www.f1-2000.co.uk/index.php?f=ignition_system

From first hand experience having brand new Bosch +4 is vs used denso coppers. The difference is in gas mileage, the denso that were in my m20 ran better gas mileage. When I stuck the +4s in it wend down about 2 to 5 mpg. I went back and immediately bought some new denso coppers and changed them and mileage was a noticeable difference.

Friend of mine on E30tech used them on his 16PSI M20. He had the same set up he started with old denso coppers and when he went to the bosch +4 it tended to flood the car. I told him to go back and buy new denso coppers or any kind of copper that isn't that cheap (aka meaning brand wise, like fuck ac delco or champions or any of that bull shit noise. He also bought the same ones I did and gaped it and the car ran like a champ.


This is my experiece for bosch +4 or any kind of platinum in car.
after this experience... I will never stick any kind of platinum anything in cars. My .02

[u3b3rg33k]

Here's a more relevant vid than I posted before:

[Vtec?lol]

It's more so about the core and the gap. Forget how many prongs it has. The M20 will run superb on copper cores and I'm guessing that;s because the coil and ecu were designed for the copper cores.
I had platinum 2 prong plugs and my car sucked balls at idle, went back to cheapo champion coppers and it's smooth!