Bosch super 4 plugs

30csl

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Is anyone running these in their m30? I have them in the csl and have no complaints but just wondered if anyone else was using them and if so which plug?

Regards,

Rohan
 
Is anyone running these in their m30? I have them in the csl and have no complaints but just wondered if anyone else was using them and if so which plug?

Regards,

Rohan
 
I had run them up until V@V when Bill R. convinced me to change them to solve a mis-firing problem (he was on the right track but it turned out to be wire related). They seemed to do very well for me and I may put them back in now that my issues are resolved.

The part I used was: Bosch Platium +4 #4479

I also have a CRANE electronic ignition unit and A Bosch Red coil.

I tend to agree with MMercury about the benefits, mostly markting hoopla. I will say that the platinum electrode should last longer and most light aircraft engines use multi-electrode plugs for added reliability. Aside from that, the coil and ignition system are a bigger influence on performance. Even then, unless you have an MSD system their benefits are also down in the fractional percentile range.
 
I had run them up until V@V when Bill R. convinced me to change them to solve a mis-firing problem (he was on the right track but it turned out to be wire related). They seemed to do very well for me and I may put them back in now that my issues are resolved.

The part I used was: Bosch Platium +4 #4479

I also have a CRANE electronic ignition unit and A Bosch Red coil.

I tend to agree with MMercury about the benefits, mostly markting hoopla. I will say that the platinum electrode should last longer and most light aircraft engines use multi-electrode plugs for added reliability. Aside from that, the coil and ignition system are a bigger influence on performance. Even then, unless you have an MSD system their benefits are also down in the fractional percentile range.
 
I will pull one of mine to see what type Bosch four it is. I have an uprated coil and the pertronix.
Thanks for the reply JH - your comparison will be as back to back as we can get so interesting to see what you think if they go back in.
 
I will pull one of mine to see what type Bosch four it is. I have an uprated coil and the pertronix.
Thanks for the reply JH - your comparison will be as back to back as we can get so interesting to see what you think if they go back in.
 
30csl,

Many thanks. I am always looking for an excuse to drive my coupe like I stole it. Doing a plug comparison is reason enough for me! I think we will need lots of comparitive data here so I may have to do several outings. I guess I will need to make a copy of my least favorite neighbors license plate to cover mine with as I go sailing past the @#@&^& speed cameras they have installed everywhere in Maryland. :twisted:
 
30csl,

Many thanks. I am always looking for an excuse to drive my coupe like I stole it. Doing a plug comparison is reason enough for me! I think we will need lots of comparitive data here so I may have to do several outings. I guess I will need to make a copy of my least favorite neighbors license plate to cover mine with as I go sailing past the @#@&^& speed cameras they have installed everywhere in Maryland. :twisted:
 
jhjacobs said:
The part I used was: Bosch Platium +4 #4479

These plugs allegedly have a wider heat range than others. I left my thermocouples at the jungle gym so I have no idea if this is fact or fancy. When I tried the same plugs for normal spirited driving in a rebuilt csi, I found the insulators were bleached white and the electrodes showed bluing - suggesting they were too hot. This seems borne out by some of the x-reference charts have that number as being the equivalent of W9DC one or two heat ranges above the recommended W8DC-W7DC. If your engine is carbed and lower compression, it may like a warmer plug. These are generalities.

Would choose Copper or Silver as a first choice.
 
jhjacobs said:
The part I used was: Bosch Platium +4 #4479

These plugs allegedly have a wider heat range than others. I left my thermocouples at the jungle gym so I have no idea if this is fact or fancy. When I tried the same plugs for normal spirited driving in a rebuilt csi, I found the insulators were bleached white and the electrodes showed bluing - suggesting they were too hot. This seems borne out by some of the x-reference charts have that number as being the equivalent of W9DC one or two heat ranges above the recommended W8DC-W7DC. If your engine is carbed and lower compression, it may like a warmer plug. These are generalities.

Would choose Copper or Silver as a first choice.
 
My engine is basically stock and has a few miles on it. The compression is uniform but I don't have a calibrated tester so I can't say exactly what it is. I will say that when I pulled the +4's to change them they had a textbook color: light light gray/tan hue patina.

Plug1.jpg

Plug2.jpg

Plug3.jpg


A reasonable reference:
http://www.verrill.com/moto/sellingguide/sparkplugs/plugcolorchart.htm
 
JJ, I will have to go pull mine now for a comparison and then bring on the back to back tests!
 
JJ, I will have to go pull mine now for a comparison and then bring on the back to back tests!
 
jhjacobs said:
My engine is basically stock and has a few miles on it. The compression is uniform but I don't have a calibrated tester so I can't say exactly what it is. I will say that when I pulled the +4's to change them they had a textbook color: light light gray/tan hue patina.
Plug1.jpg

Plug2.jpg

Plug3.jpg

Here is another chart based on? common sense? http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

You do not indicate how many miles/years are on those plugs, driving conditions, fuel etc. I am no expert. If that's what your plugs look like after a trip around the block then the charts are not particularly helpful. On the other hand, if you have 100k on those air gap zappers, everything is terrific. I am still not sure your pictures are anymore than a tacit endorsement since you are not comparing the results with other "standard" type plugs or single, double or even triple electrode versions.

I recently pulled some BP6ES plugs with 4500 miles on them from a stock csi. Gapped at .042 with accel ignition set up. Do not have a picture but they looked virtually spotless. Insulators were off white and no deposits even on the inside shell to speak of. Wish the rest of the car looked clean. I cleaned them (mostly the threads) filed the center electrode flat and reinstalled. As I recall, the 4479's (which were originally to be installed in a Mercedes) produced an occasionable rough idle after seeing high rpm and when the engine was particularly warm. Slight pinging too when the temps were up. Not the case with colder plugs, hence the variety of different plugs.

Whether your plugs would fare better in my engine or vice versa remains a mystery for the ages. Different engines, conditions, driving styles may make a difference.

Tally ho!
 
jhjacobs said:
My engine is basically stock and has a few miles on it. The compression is uniform but I don't have a calibrated tester so I can't say exactly what it is. I will say that when I pulled the +4's to change them they had a textbook color: light light gray/tan hue patina.
Plug1.jpg

Plug2.jpg

Plug3.jpg

Here is another chart based on? common sense? http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

You do not indicate how many miles/years are on those plugs, driving conditions, fuel etc. I am no expert. If that's what your plugs look like after a trip around the block then the charts are not particularly helpful. On the other hand, if you have 100k on those air gap zappers, everything is terrific. I am still not sure your pictures are anymore than a tacit endorsement since you are not comparing the results with other "standard" type plugs or single, double or even triple electrode versions.

I recently pulled some BP6ES plugs with 4500 miles on them from a stock csi. Gapped at .042 with accel ignition set up. Do not have a picture but they looked virtually spotless. Insulators were off white and no deposits even on the inside shell to speak of. Wish the rest of the car looked clean. I cleaned them (mostly the threads) filed the center electrode flat and reinstalled. As I recall, the 4479's (which were originally to be installed in a Mercedes) produced an occasionable rough idle after seeing high rpm and when the engine was particularly warm. Slight pinging too when the temps were up. Not the case with colder plugs, hence the variety of different plugs.

Whether your plugs would fare better in my engine or vice versa remains a mystery for the ages. Different engines, conditions, driving styles may make a difference.

Tally ho!
 
CIMG1721.jpg


CIMG1722.jpg


Here are the ones out of mine - they are about 8 yrs old - done about 5k miles. Last time it ran though it was a start stop job to move it. I have cleaned them once or twice in between.

Last time i removed them they were more white in colour.

They are Bosch W78 - what is that like for heat range etc?
 
CIMG1721.jpg


CIMG1722.jpg


Here are the ones out of mine - they are about 8 yrs old - done about 5k miles. Last time it ran though it was a start stop job to move it. I have cleaned them once or twice in between.

Last time i removed them they were more white in colour.

They are Bosch W78 - what is that like for heat range etc?
 
You do not indicate how many miles/years are on those plugs, driving conditions, fuel etc.

My intent was not to endorse anything, tacitly or otherwise. I'm just sharing information in response to a question simple question.

My plugs have about 2-3K miles and they were pulled At V@V - a 300 mile highway trip following by the morning 1 hour drive through country roads. This is a good set of usage conditions to inspect plugs. I fill up with premium fuel although my engine doesn't need it; questionable benefit but I tend to think the higher grades have less ethanol and more engine protecting additives. My +4 plugs have been in a bag since I pulled them and I took the photos this morning.

I have heard several people say the the M30 doesn't "like" platinum plugs but mine have not exhibited any problems. Personally I think a plug is pretty much a plug for street driving and the best bang for the buck in an electronic ignition, especially and MSD.
 
You do not indicate how many miles/years are on those plugs, driving conditions, fuel etc.

My intent was not to endorse anything, tacitly or otherwise. I'm just sharing information in response to a question simple question.

My plugs have about 2-3K miles and they were pulled At V@V - a 300 mile highway trip following by the morning 1 hour drive through country roads. This is a good set of usage conditions to inspect plugs. I fill up with premium fuel although my engine doesn't need it; questionable benefit but I tend to think the higher grades have less ethanol and more engine protecting additives. My +4 plugs have been in a bag since I pulled them and I took the photos this morning.

I have heard several people say the the M30 doesn't "like" platinum plugs but mine have not exhibited any problems. Personally I think a plug is pretty much a plug for street driving and the best bang for the buck in an electronic ignition, especially and MSD.
 
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