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Bosch Platinum +4 vs. AC Delco

Bosch Platinum +4 VS. AC Delco

  • Bosch Platinum +4

    Votes: 5 5.6%
  • AC Delco

    Votes: 79 87.8%
  • Other

    Votes: 6 6.7%

  • Total voters
    90

wegel11

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Im running a new rebuilt 350 with only about 1K on it so far, but when i put it in I bought into the hype of the platinum 4's. The engine runs "good" but I think it should run better, have more power, and be more efficient. Every thing on the engine is new, including the HEI. I was wondering your opinions on if i should keep running the Bosch or get some AC Delcos
 
The last set of delcos I bought, 2 of them were weak fire out of the box, brand new. Went checking my coil, module, brand new wires, checked for spark it was there, but bought a new set of bosch platinum (not the +4, just the "regular" platinum) and she ran perfect. Curiosity got the best of be, so I started swapping one delco in at a time, finally determined 2 of them were not firing as they should.
ANyhow, I used to trust the delco name, perhaps not anymore. ANyhow, I don't think the plugs (all good plugs that is), wheter delco or bosch or going to yeild you any noticable increase in power or mpg. If you were runnig 1/4 mi's, mabey a little 0.1 of a second, but in a driver, you won't notice it.

Keep in mind, a 1000mi engine might not be broken in yet, what type of rings are in there, if plain cast, it could take several thousand before they seat right and engine is at full power and effciency. Is it using any oil, a new engine normally will.
 
I'm not against aftermarket or other brands. I know that there are probably some really good parts out there that are not what the factory chose to use..

But, I myself preffer to use AC Delco. Theres just something about using the parts that the engineers designed for it... or at least the brand of plug. For instance I would not have a problem going with platinum AC Delco's ... but I've gotten away from using any other brands for a long time now. Realisticly there may not be any difference .. and then again maybe there is. I just chooce AC Delco and leave it at that.

Just my 2 cents.
 
dude i had the bosch 4+ platinums too and if i were you i would throw those the hell away from your motor they belong on a cheap rice rocket not on a v8 i switched to the ac delcos and holly **** big noticable difference right out of the garage my 355 tbi also has low miles at about 5000km :D
 
Agreed, I've tried all those plugs (splitfires, +4's, Bosch Platinum) AC Delco plugs haven't let me down and they're a hell of a lot cheaper. I agree with engineering part, I use AC Delco oil filters, too. They actually filter WAY better than Fram.
 
Im not crazy about the Bosch design at all. I used to work at Trak, and I would regularly see Bosch plugs come back in with a comment of the car running worse.

Part of the problem is the hair-sized platinum center electrode. If you burn any amount of oil, it will foul. Nearly any other plug on the market has a bigger center electrode.

Another problem is their generic heat ranges. They do not have application specific electrode depths, so your heat ranges desiged to be used for your engine are more of an approximation. They do that to cut down on the number of different plugs they make.

The only benefit I can see from using platinum plugs is the lack of wear on the platinum surfaces. Bosch, unless they changed their design fairly recently, has only one platimum surface, the center electode. That leaves the side electrode to corrode faster. Even with the +4 design, you still get the hair-sized platinum center electrode. Instead of a strong spark between the center and side electrode on a conventional plug, you get up to 4 weak sparks on a plus +4 plug. I have been told theat there is negligable difference between the two.

A double platinum would be best. Autolite makes those, and I use a set in my dads Ranger. They have a 5 year warranty, and its probably been that long already, and they still work pretty well.

All in all, I would not recommend anyone to use Bosch Platinum plugs. When I worked at Trak, regular Bosch were $0.99, Platinum at $1.99, and Platinum +4 at $5.99. I would run and still run ACDelco conventional plugs, CR43TS, in my 88 TBI. I have not noticed a problem with the plugs yet. I have been conidering a switch to ACDelco platinum, but if and when I do, I will post up a review of them.

Sorry for the long post
-Randy
 
Use what GM uses!

I've posted before how I hate the Bosch Platinum plugs(+4 or not)..we had several cars at my friends shop actually run WORSE after a tune up when we installed Bosch platinum plugs!...most of the cars that "rejected" them had one cylinder that acted like the plug wasn't firing--removing and inspecting the plug showed no abnormalties,but put the old plug or a new AC plug in,and it ran perfect again! :screwy: ..

So we started telling customers if they brought their own plugs for us to install,to bring AC plugs,like GM uses factory..I've used AC or Auotolite plugs since I was old enough to unscrew one from an engine,and have had very good luck with them..can't vouch for their quality now though,since they are "Hencho En Mexico" made like everything else nowadays..

I think Platinum plugs are a waste of time and money in your typical Chevy small or big block motor thats carbuerated...they only seem to work in cars designed for them from the factory,like DOHC V-6's,and cars that had them as factory equipment....I'm not a fan of Champion plugs either!..I've gotten several free lawnmowers from the dump that needed only a new AC or Autolite spark plug,a fresh tank of gas,and a few good tugs on the rope to get them running!..(when you only have 1 spark plug,and 1 cylinder,the plug HAS to be a good one!)..Champions seem to foul,then NEVER fire again!--but the AC and autolite plugs will "recover" after being flooded or fouled... :crazy:
 
my bb likes ac delcos...it didnt like the spendy bosch plugs....
I agree with the engineering comments....
in this case the best upgrade is factory stock!!!

cam
 
73k5blazer- The rings are chrome molly, and it does not seem to be burning oil, if it is, its not much at all.

I think I am going to give the AC's a try, any ideas on what to use those $6 Bosch's for. :whistle:
 
Ive been told that platinum is actually a poor conductor of electricity, so i guess they're just designed for certain engines and longevity. :confused:
 
Regular old autolites

I do probably 2-3 tuneups a week here at the "garage" and I use nothing but regular autolites they run forever and have never let me down.I personally think it's user preference when it comes to plug brands, (cept platinum and more than 1 electrode plugs, these all suck) autolites are inexpensive and last a long time, I even put them in my own vehicles! :D
 
i use TSX series ac delcos, longer tips, electrodes further into chambers,

all i ever run always good runnign engines with them

i have no luck with autolites either, in chevies anyways,


good luck
 
Platinimum plugs = Your hard earned money going to a big corperation. And them laughing all the way to the bank. Ha. Ha. Ha. ha. :laugh:
"There is a sucker born every minute" PT Barnum :wink1:

PS...... I use AC Delcos! Even in my Ford. :p:
 
It's not a good idea to use something that wasn't intended to be used. I have seen engines with platinum plugs burn holes through pistons that weren't designed to use platinum plugs.
 
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I have delco platinum plugs in our '99 S-blazer and '98 Boneville. Both went 100K or more on the original plugs. The blazer uses the standard looking style platinum and the Boneville uses the small hair sized electrodes. Platinums do work, I used to change plugs out ~30K on the 3800 engine(at the dealer) and see noticealbe burn on the electrode with standard plugs.

That being said I always tried to recommend Delco parts, that however is changing. Their oil filters are now made in mexico, instead of Flint, MI. There is a visual difference between the USA and mexico filters with several noticable production differences. Since the outsourcing of filters I have had oil leaks at the filter housing on more than one occasion, was not an issue with the older US style. Now I run fleetgaurd or Donaldson filters. Now Delphi has announced it is going to close the Flint east facility that makes spark plugs, guess I need to find another supplier for plugs now :mad: .
 
I had an 87 S10 with the 2.8, and the only plug it ran good with was the bosch platinum.

Everything else I've owned liked the AC's much better.

Tom
 
someone made a comment about "4 weak sparks"? with the +4's,,,,,

i always thought, and have been told, that electricity takes the shortest path possible to complete it's arch or travel.

just because there are 4 electrodes, does not mean you are getting 4 sparks,,,the spark just jumps around more on those 4 prongs, IF at all. It will find the closest electrode and hit that one most of the time anyways.
You're not getting any hotter of a spark, or more of it just with plugs, that is accomplished with hotter coils and igition generating components.

those plugs are
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a few years ago, i ran some of the Splitfires, just because they were free to me, and i really didn't notice any difference with power, or fuel economy.

still, i drove on them for about 2 years before i decided to change them out, still could have been uses awhile longer but definately showed signs of wear.

been using Delcos ever since, no problems.
 
Now Delphi has announced it is going to close the Flint east facility that makes spark plugs, guess I need to find another supplier for plugs now
Yeah really sucks AC Delco is outsourcing parts now. Their quality is definatly going down hill.
Guess I'll be using Motorcraft ftom now on. Winsor 5.0 plugs work great in SBC :thumb:
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Chevys too!
 
Platinum is actually a great conductor of electricity, in fact I was told by a friend taking an automotive engine theory class that hte electrons will actually flow more readilly jump the the gap reducing the effective spark. He also said that most of the drag racers (weekend warriors) have found the regular old plugs to work better.
That said I do know that modern jet engines use platinum in their ignitors but that probably has more to do with the extreem spark and temperatures they have to endure.
As far as what to do with the old plugs I know on the a/c ignitors their is about $50 worth of platinum in each. You might check to see if you could mine enough platinum out to be worthwhile. But usually the trash can is the best receptacle of those old "good" ideas :D .
 

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