Any happy Bosch Platinum +4 users?

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Aug 30, 2004
Any positive experiences w/this product?

If so, please list the year/make/model of the car, as well as the # miles you have on the plugs.

I'm curious as I've heard VERY mixed reviews.

Price is $5.99/plug, w/$10 gift card offer for every 4 you buy.

I ran them in my 1993 5.0 Mustang for a few hundred miles...nothing special. Tried them in my truck (2000 F-150) and they wouldn't hold up to boost without the spark breaking up, same with a set of NGK TR55IX iridiums. Went to a set of NGK copper plugs and they've worked great. Overall, unless you have some serious performance work done, stick with properly factory plugs and stay away from gimmicky plugs.
My father used them in his '92 Ford Bronco 351. He probably ran them for 40k mi before trading the Bronco in. He loved them in that vehicle. They increased his mileage by 1-2 MPG -- which was very helpful. His Bronco had other mods: chip, intake, Jacobs ignition, etc.

You will find mixed reviews for these plugs. Neons for example do not like Platinum plugs. It depends on your application.
I used them several years ago in my Volvo. Initially, I was impressed...smoother idle, also smoother throughout the powerband. But I found out that they did NOT like cold starts when below freezing. I switched to NGK Iridiums...problem solved.
The Bosch four prong plugs are more hype than improvement. I used them with great success on fuel injected european cars.Customers loved them, but there was no performance improvement that I could measure. They tended to foul easily on carbureted cars.
I had a set on both my Caravan and my wife's Jeep for a while. Nothing noted, performancewise, good or bad. In the jeep the OEM plug was so much longer that I went back to be sure that the guy gave me the right ones. They have too few part numbers. In the Caravan, I believe I used the same set over a couple of years.

About the only thing that I'd like to try is those "truck plugs" that just feature larger conductive surfaces. Otherwise it's OEM numbers for me
Ran them in a '96 Maxima without much problem or improvement. Replaced them with the OEM spec NGK's - car seemed to like them better (slightly better idle/accel). The OEM "double platinums" have a list price of $17 EACH.

Still, with plugs, I've decided it's best to stick with the OEM part.

Companies use dual prong plugs, as evidenced in my E30 BMW.

Companies also use high end platinum/iridium plugs for maintenance reasons.

They are widely used, and the basic technology is good. How much of a gimmick 4 prongs, or how fast advantages deminish is another issue.

Put as many ground electrodes on a spark plug as you like- it's still gonna throw *one* spark from(to) *one* ground electrode when it fires, & all the others just get in the way of of the spreading "flame". You'd be better off getting an all/"double" platinum plug in conventional configuration- if your engine is one of the rare ones that may actually run better on platinum plugs. In most applications, platinum plug's advantage is that they last longer- not that they run better.
(though I'll concede that for almost all of us they run good enough)

Want some bargain priced plugs that seem to run great in almost everything? Try some copper core NGK "V-Power" plugs. When I bought my last set a few months ago they were even cheaper than plain old Champion copper cores. My old Neon runs great on those too!
I just removed the +4's from my 4.0 Ranger. They seemed to be good a first, but over the last year, I had a lot of stalling problems at red lights. Couldn't figure out what it was until I read on another sight that a guy had the same combination/problem and that new plugs fixed it.

NGK Iridium IX's went in this time and made a noticeable improvement in power. NO stalls since the replacement.

No more Bosch plugs for me.
Worked great in my 98 F150 4.6l v8. So good I put a set in a 4.0 OHV Explorer, ran like crap, stumbled, lost milage. Now happy with Autolite in both. The word on the street, no Bosch in Fords with the lost spark ignition systems.

Stuart Hughes seems right on in his post^^.
I also add that I don't like multiple electrodes, as they block/inhibit flow in and out of the critical spark area.
Found on Autolite, Bosch, and a story on Nascar's website single platinum spark plugs and Waste Spark Ignition systems are incompatible. If you have a coil pack that has multiple coil towers not Coil On Plug but a separate coil pack with all or sometimes 1/2 of the engines wires on it that fires 2 plugs at a time the backwards plugs have been known to shed out the platinum causing premature gap erosion. Must go to Double Platinum or copper plugs. Irdium are fine too but you may have trouble with iridium to platinum.

Originally posted by dailydriver:
Critic; what make/model/year/engine are they potentially going into??

BlownF150; have you ever tried those Czech Brisk plugs?? Supposedly many with various boosted mod motors have had good luck/slight power increases with them.

I've heard of them but never tried them. Think a guy with a turbocharged F-150 tried them and it wasn't much improvement over the Motorcraft copper plugs he was using. As far as I know with these motors it's best to go with copper plugs or very narrowly gapped iridiums when it comes to boost.
Many years back I had an 86 Ranger 4x4 that ran happily for mebbe 125,000 miles on Autolite Platinums (after the first early change). In the meanwhile I changed out plug wires, rotors, dist caps. I had a little stumbling at low speeds, found a bad whire, was replaced under lifetime warranty, so I bought some more plugs while at it. I went with Bosche Platinums and was never quite happy. They just didn't seem to be right in this application, after mebbe 10,000 miles I reinstalled a set of Autolite (I believe double platinums) and ran another 50-60'000 miles before trading that truck in on another. My experience in THAT truck made me intend on using the Autolites.
I am planning on changing plugs soon in my Porsche, I'd not shy away from trying them again, am leaning to trying the newer Iridium plugs. My mech says stick with copper, I'm thinking trying something new.
I used em in two Civics and an Accord. Usually gained 1 1/2 mpg. Changed em once a year. About 30,000 mi. Seemed like a good plug.

Originally posted by The Critic:
Any positive experiences w/this product?

Tried them in my 86 Toy 22R and they were "ok". Got about 30k out of them and they looked like crap.

Went back to Denso for $1.00 each. Truck runs the same.

Save your money IMHO.
My E30 BMW uses dual prong copper plugs... I believe OEM was tri-prong!

Others have tried fewer or more prongs, and different electrode materials with mixed results.

I am running single prong platinum bosch plugs inmy mother's 97 Plymouth Breeze. They run fine and smooth, like the copper plugs they replaced.

Critic; what make/model/year/engine are they potentially going into??

BlownF150; have you ever tried those Czech Brisk plugs?? Supposedly many with various boosted mod motors have had good luck/slight power increases with them.
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