Bosch Platium Spark plugs?

Got a 200 sl1 and Saw these on sale at my local Canadian Tire for 4 bucks off a package of 4. I tried them out and defiantly an improvement in torque and smoother acceleration (5 speed manual and tons of hiway driving).

I should also note I changed my PCV valve which was grungy and oily so maybe that has some influence too....

Any long term implications of keeping these things for 35000 to 50000 KM? do they ruin valves, piston score etc? What about fuel Consumption?

Thanks for any input

Reply to
Canaan Apollyon
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Yeah replace any old worn out plug and you would get that. Bosch plugs in my experience have been nothing but crap in the long run. The platinum slides down and sometimes falls out and they also foul out easily. Best bet is to get autolite platinum or ac delco.

Platinum plugs are supposed to last 100k "miles" and cause no damage to the engine unless the platinum falls out of those "bosch" plugs then yeah you'll get damage.

Reply to
Blah blah

I knew a search would come up with something.

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This guy seemed real happy getting new plugs from bosch. I'd be happy to get my money back rather than more frigg'n crap. I need to take pics of the ones I got sitting on a shelf. I know other people that have had problems with bosch plugs. I dont think bosch has been in any hurry to correct anything.

Reply to
Blah blah

I've owned my Saturn for 11 years now, and have witnessed a good number of parts dyno tested (on almost a hundred cars), and have to say this -

The only way any spark plug is going to make a difference in a naturally-aspirated Saturn motor is if the old ones seriously needed replacement, or there was something wrong with them. That's just my opinion, but it's based on what I've seen.

FYI - you can see several hundred Saturn dyno runs in the dyno archive at

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Lane [ l a n e @ p a i r . c o m ]

Reply to
Lane

Someone mentioned 100K miles plugs. Does Saturn still use aluminum heads?

I wonder how easy a spark plug will come out of an aluminum head after 100,000 miles? Will they come out with or without the threads?

James

Reply to
James1549

Yes, the heads on the S-Series engines have always been aluminum.

If the plug is put in using anti seize compound, when the motor is cold, and tightened to the proper torque spec, I'd assume it would come out without a problem.

Changing plugs is so easy and the NGKs that the dealer sells are so inexpensive, I take 5 minutes and change them out once a year. Costs less than $10 and don't have to worry about wear, longevity, or the issues you mentioned.

Lane [ l a n e @ p a i r . c o m ]

Reply to
Lane

Virtually all quality plugs come with chrome platting so they arent often hard to remove even without anti seize thought i still use it. I mentioned 100k plugs and 100k is pushing it so let me rephrase that. Platinum can last "upto" that long but I suggest replacing double platinums at 80k and wires at every 40k.

Reply to
Blah blah

I did plugs recently on my 97SL2 - used the NGK's from SPS. One model was slightly warmer and the other slightly cooler. Do you remember what that refers to and or what it means related to performance?

I've got the slightly cooler 6953's and the only difference (which could be various technical points and or my imagination) is that it feels like the timing is a little retarded when the car is not up to operating temp.

I've noticed over the years the intermittent and slight loss of power (like when you switch on the AC) and have never figured it out. It's not detectable under normal driving - I'm talking a full throttle 3rd gear scenario on a freeway onramp where you're putting 100% load on the engine. I've read a stretched timing chain can retard the timing, but I'm thinking it would be a constant and not intermittent condition. Still a pretty amazing little motor with 116 cubic inches, 90,000 miles and my lead foot.

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Reply to
Jonnie Santos

Unless your original plugs were shot or defective, there is no reason that the Bosch plugs should have made any significant difference. With OBD-II compliant systems, any significant misfiring should be detected. If youi didn't have a check engine light before replacing the plugs, it is unlikely you had a misfire problem - i.e., the plugs you had before were doing all they could. New plugs couldn't do any more. I have had problems in the past when I changed brands of plugs, becasue the replacements were not of the correct heat range, or had the wrong resistance value. Persoanlly, I now stick with the plugs that were original equipment or specifically recommended by the vehicle manufacturer. I learned this the hard way on a Honda. OE plug were fine. I installed Autolite Platinum Plugs (the ones Autolite recommended, not Honda)and got a check engine light within a day. I cleared the code several times, but finally changed to AC Rapid Fire Plugs (the one recommended by AC, not Honda). Within a day, check engine light was back. I finally got the NGK plugs specified by Honda - no check enigne light ever again. I have also been warned that Fords don't like the Bosch plugs. I've never tried them, but given the low price of plugs, I plan to just stick with the OE type.

Regards,

Ed White

Reply to
C. E. White

Hotter or colder mean literally that. Hotter plugs have tips that get hotter as the engine warms up. Colder plugs have better heat conduction properties, so the tip is cooler.

This was more important in the past when the spark was weaker. A hotter plug is less likely to foul (the depositis burn off), but it is more likelt to cause pre-ignition (knocking). A plug that is to cold might lead to missing - particaulrly in the old days when ignition systems were much wealer than today. Temperature range can be critical in racing engines that run for extended periods at high power levels. Plugs that are too "hot" can get so hot that they can cause severe preignition. Plugs that are too cold can foul out at low speeds.

When you are talking about high perfomance engines that are at the edge of the performance envelope, a lot of weird things are done with spark plugs (minor changes in heat range, indexing, etc.). FoOr street cars most of these sorts of fine changes would be undetectable.

See

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Regards,

Ed White

Reply to
C. E. White

Good info and links - thanks. I pulled this from the first link...

"The heat range of a plug does not affect the power output of an engine. Rather, it allows the plug to function as designed for the duration of the racing event. In other words, once the correct heat range is found that prevents fouling and does not contribute to the pre-ignition or detonation, a change to a hotter or colder plug will not have a positive effect on engine performance. "

Reply to
Jonnie Santos

Only furthers in my mind the adage:

"You can always tell a German; You just can't tell him anything."

My son-in-law worked at Zeiss (a German owned company) where that saying was widespread.

In my own dealings, I had designed a commercial ballast for an arc lamp. It was designed to Osram's published specifications for one of their lamps. For years these ballasts worked just fine. Recently, there have been some problems experienced by customers and I tried to resolve any issues with Osram. I even sent one of my ballasts to Osram to have it reviewed. The report came back that the unit was 'satisfactory for use with their lamps." No mention of possible trouble causes was made and they skipped over entirely my assertion that their Japanese competitor's product totally outperformed the Osram product.

Lest anybody think I am German bashing, Oppie is short for Oppenheimer and I work for another German company.

Oppie

Reply to
Oppie

Just as a precaution, I always squirt a bit of Kroil

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on the base of the plugs and wait 10 minutes before trying to remove them. Kroil is a great penetrating fluid.

Previously, I had stripped the threads in the head. Repair wasn't too bad. Went to the parts store and got a tool to re-thread the hole oversize and a steel insert that screws onto the plug and into the head. (Lisle made it afik) Carefully tap the new thread (this is no time to learn if you haven't done tapping before). Helps to have the piston slightly down to keep it out of the way. Blow out any chips that remain in the cylinder. Degrease the surfaces and apply a small amount of stud lock to the sleeve exterior and using a spark plug, thread it into the head. When the locking compound has set up, the plug can be removed and a new one with anti-seize on it can be torqued in.

Oppie

Reply to
Oppie

If you ever have to tap threads for something like a spark plug hole its a good idea to put something like crisco on the tap. It will catch a lot of the shavings and chips.

Reply to
Blah blah

I hurt the threads in one of my plugs awhile ago......I was removing one of the plugs when all of a sudden it wouldn't turn anymore, I tried working it back and forth, no luck......I ended up having to use a big breaker bar to get it out.

The good news is, I just used a thread chaser and it fixed the threads, no problem. No need to tap it bigger or anything.

Reply to
BANDIT2941

Often, a bit of aluminum will stick to the steel threads and cause the plug to jam. Forcing it just allows the aluminum chunk to tear at the rest of the thread. You were very lucky just to be able to chase out the thread.

Reply to
Oppie

ALWAYS use a good thread lube when putting spark plugs into an aluminum head! Molykjote is good, as is Champion Plug Lube, available at airport pilot supply shops.

Reply to
Orval Fairbairn

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