Bosch Platinum Spark Plugs

[herrhaus]

I always use OEM plugs. That way I know that they have the correct resistance characteristics and heat range.

Below is an excerpt from a post in the ODYCLUB. I though that I'd share:
"Many folks believe that some plugs run "hot". This doesn't mean that the plugs apply or transmit a higher voltage. What it refers to is the spark plug's ability to dissipate the heat of combustion. If the Bosch plugs truly run hotter, it means they have a longer ceramic insulating nose exposed to combustion gases, and less material available to conduct heat through the heat conduction path made up of: plug body-plug threaded area-cylinder head spark plug hole threaded area-cylinder head.

If that is the case, they will run "hotter" (i.e., sustain a higher temperature at their tip). This is good for keeping the plug clear of deposits, but can be a problem if it causes the insulator to blister or melt the electrodes. Then there's the added problem of pre-ignition/detonation, which is not good for any engine, but is especially damaging to aluminum engines (specifically the aluminum cylinder head, not the steel cylinder liners)."

I plan on picking up a set of Motorcrafts for the tortus this week.

[cheetoh69]

Well if you have a VQ35DE under the hood the Bosch +4 Iridium are awesome. Especially with timing set at 18 degrees.

[jndejure]

Ran Bosch +4's in a 96 Vulcan with no problems whatsoever. But, I did change to Bosch Premium Wires also. The ones with the stainless coiled center wire. Might have something to do with it. The Bosch's ran smooth, ran economically, and had great pull with no hesitation. Haven't tried them in my Duratec powered Sable yet, but probably will given the good luck with them so far. I even installed a set of +2's in my friends Lincoln 4.6 and he is still a friend! Also, all plug ends and connectors were well lubed with dielectric grease, which may have helped. If you do replace your wires, don't skimp on the quality, get the premium wire set. Basically all of the brands use the coiled stainless center wire in their premium wire sets. Just make sure the ones you get are the good ones.

[2000sable]

Been running Bosch platinum iridium fusions for five years in a windstar and my sable duretec zero problems and the cars run like a top with these plugs.

[mooby]

we are talking here about the +2 and +4 they cause prb

the rest off the plug work great

and in some engine like my 3.8 taurus / mustang hybrid well it suck so it all depend

[JohnnyO]

I spend most of my time on a few Ford truck boards where the subject has come up also. Bottom line, the Bosch +2 and +4 do not get along well with the late-model Ford ignition system because of the multiple electrodes.
Also FWIW, a platinum or double-platinum plug offers no performance gain over an old-school copper plug, their advantage is simply that they last longer.

[clgielin]

My stock Motorcraft plugs and wires didn't make it to 50k in my '02 duratec. I was grounding through the plug boots and the ground electrode was eroded. The only codes the Taurus threw were random misfire and cylinder 6 misfire. I changed the wires to some premium NAPA wires and threw the Motorcraft plugs in the trash to install a set of Bosch +4's. 110k later, I have yet to have a problem with anything to do with the ignition system. I do not run premium fuel, driving is mixed city/highway and all regular maintenance is performed in my garage. The only noticeable change in performance happened when I moved to an elevation of 4200 feet.

Spark plug temperature range seems to carry the same mystery as grease compatability and the aspect ratio on metric tires! If you want some info on plug temp ratings, try ngksparkplugs.com.

[jndejure]

"clgielin" I believe has it right. He used premium wires when he installed his Bosch +4's with no problems. Let's start pushing the need to do the best job we can when working on our Taurus/Sables. Changing plugs is no exception. Let the engine cool down. Clean the plus recepticle out with compressed air. Use an anti-seize grease on the plug threads and a torque wrench when installing the new plugs. Premium wires and sufficient dielectric grease should also be used.

About a year ago my brothers Saturn was running rough, so he changed plugs and installed a premium wire set, yet the problem persisted. He asked me to take a look and I did when it was dark. And, there it was - the coil plug wire closest to the block was jumping spark. Since I knew he had put a good set of wires in I simply used dielectric grease on all coil ends and later plug sockets also. Now you can look at the motor after dark without seeing a light show by the coil pack. Since then I am a firm believer in dielectric to keep moisture from sneaking up under those coil and plug end boots.

[mooby]

yes agreee but it wont change a thing

our engine dont like bosh +2 and +4 plug

[clgielin]

The 3.8L must be picky engines. They don't like bosch +2's, +4's or head gaskets?