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

 

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.

 

I knew a search would come up with something.

http://www.deathstar.org/~flash/bosch.html

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.

 

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
http://www.saturnperformanceclub.com.

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

 

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

 

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 ]

 

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.

 

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.

 

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

 

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

http://www.edelbrock.com/automotive/sparkplugs.html
http://www.tpub.com/content/construction/14273/css/14273_64.htm
http://www.densoiridium.com/heatranges.htm

Regards,

Ed 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. "

 

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

 

Just as a precaution, I always squirt a bit of Kroil www.kanolabs.com 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

 

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.

 

Previously, I had stripped the threads in the head. Repair wasn't too bad.

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.

 

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.

If it doesn't feel right at the start (and a lot of the times, I do it
anyway) I use a squirt of good penetrating fluid like Kroil then let it sit
a few minutes before proceeding. In spite of all the advertising, WD-40 is
nearly useless.
Oppie
_________________
|
| 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.

 

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.