spark plugs for my 850?[ALL/1988] posted by Paul Elliott on Tuesday, 17 February 1998, at 8:15 a.m.

Could someone please help me out regarding the choice of plugs for my '95 850 turbo with IPD ECU and Exhaust?

The Volvo service manual says to use either Volvo plugs (which my dealer wants to sell me for over $6.00 ea!), or its
equivalent which they list as Champion RC 7 GYC.

The first autoparts store I went to looked up my car in the computer, which came back with a Platinum Bosch
plug...Now, I've read in numerous places NOT to use platinum plugs with my engine. He then looked in another source
and came up with Champion, but in a 9 range...Now, I assume that in the Champion 'equivalent' which Volvo suggests,
the 7 in the number specifies the heat range? So, when the autoparts guy reported to use a '9' that hes saying his source
says to use a higher heat range?

Why all this discrepancy? Does it mean that it really doesnt make a difference?

In addition, IPD sells a Bosch plug for ALL 850s, as well as the 960. And, it is the same plug for all models of 850 and
the 960. Whereas the Volvo literatures lists Different plug types for Turbo and Non-Turbo engines?

So, I'm most confused...I suppose the safest would be to buy from the dealer, but at $6.32 ea, I'd rather find another
source. Thank you.

Volvo now uses Platinum tipped plugs on Turbo, not the platinum as Bosch makes it with a subsurface electrode, but
with platinum discs fused to both electrodes. The non-turbo plugs are three ground electrode type plugs.

So, I wonder how IPD can accurately sell the same Bosch plug for all 850 Applications? When I asked on the phone,
he said, 'Well, we're selling the same plug we use in our Project Turbos, and We've had no problems, so....'. I told him
that this wasnt a real good answer, and let it go..

Perhaps your answer explains why the plugs are over 6 bucks from Volvo dealers...I sure wish there were an
equivalent we could buy from a parts store, though. Any ideas?

What about that Bosch platinum plug...even though its not the same application of platinum which Volvo uses, maybe it
would work well as a replacement plug?

And, as far as the Volvo lit goes, the Champion plug they say to use, the RC 7 GYC isnt even available from them
anymore....Champion only seems to offer an RC 9 YC now! Geez, I didnt realize buying plugs was so complex!

Volvo is pretty finicky about the plugs they put in the white motors. Go to the dealer and get the latest and greatest.
You could end up buying the "cheaper" ones and then still having to get the correct ones. If the plugs were $15 a piece,
I could understand your reluctance.

Do you also buy the cheapest tires that will fit your car?

Mark, if you looked at the amout of money I've given to IPD, I dont think youd say that! Anyway, its not a question of
trying to find the cheapest plug around. After all, I use Mobil1 every 5K miles, bought a $1000 ECU, $500 Sport
Exhaust, and Sport tuned Sway Bars, so I have no problem buying the best where it makes sense....In this case,
though, I raised the question because Volvo in their technical literature stipulates what plugs should be used....they list
the Volvo kit number for the Volvo labled plug, which is the $6.32 plug, and they list the Champion RC 7 GYC plug as
the equivalent to buy....That plug, though is NOT available in the states....Champion lists the RC 9 YC as the
equivalent, but I dont want to go a higher heat range....Besides, I'd prefer Bosch...Now Bosch's 'equivalent' is the
FR7DC, which is what IPD, Trollhatton, and most other Volvo suppliers use for the 850 Turbo....Now, logic should
tell you that if the Volvo plug was sooo special as to justify a price differential of 600%, then they would NOT list an
'ordinary' champion copper plug as an equivalent...and, since we're talking about copper plugs, I can see no reason not
to use the Bosch which , again, IPD sells with impunity and uses in all their project cars...

So, that's the logic I use; NOT the logic of cheapest regardless of quality...again, if you see a flaw somewhere in this
thinking Please advise, for it escapes me at the moment..

Hi all,

Ive got an 850 20valve. I've personally swapped to the new Bosch FR56 super4 plugs which have four electrodes
instead of the normal one. Its suppose to work out the least resistance, and give 200% improvements in cold starts, and
other benefits. They have a warranty for a year with them, i dont know if you can get them yet in the US. I paid here in
the UK for them approx 22 pound including tax.

Mark.

I havent seen that number here yet...The Bosch plug everyone wants to sell me here as the stock plug equivalent is the
Bosch FR7DC which sounds like its one heat range warmer than yours....I believe yours is that one range colder than
the standard 850 plug....did you plan it that way, or just not aware of it?

Hi paul, all.

The information on the packet which contained my Super4 spark plugs is as follows:

Bosch Super4 FR56 (all models) part number 0 242 242 501 for a pack of 4.

"Optimum performance and improved efficiecny through surface-air-gap technology. The plug itself chooses the best
route for the spark to ensure safe ignition. Guaranteed for 1 year.

Below is a crude representation of my picture on the box two gap that can be seen
in profile (and of course two more are actual either side unseen totalling 4).

a = air gap. b = surface-air-gap.

cathode

Electrode b Electrode

     |--- | ---|

        | a | |

    | -------- |
    Base | |

As i already mentioned in the previous note they are 200% better on cold starts, beter fuel economy and longer...... life.

Hope this helps. The distributor here in the UK are our main Auto accessory shop of Halfords and Bosch service
centres.

i used to always use the champion myself twin copper cores before this as i dont wait around for the extended time
between changes Volvo recommend myself, depending on how much driving and style of terrain.

Mark.

1994 . 850 glt 20v

If IPD is correct, that their Bosch plug is good for normally-aspirated and turbo 850s and all 960s (which I assume
your owner's manual says is a Bosch FR6DC, since that's what my '94 960 uses), and you want a cheap plug, you can
use a Motorcraft AGSP32C. Be forewarned. My 960 ran OK with the Motorcraft's (which I had the auto parts guy
"throw in" when I bought a bunch of goodies at my last maintenance orgy), but it did not idle smoothly -- had a slight
"bump" every couple of seconds as I sat at a stoplight. I put fresh Bosch plugs in and the car idles as smooth as ever.

I always try to stay with Bosch replacement parts with all the Volvos I own or have owned (nine, so far) and have
never had any problems. Don't try to save a buck or two, go to a "name brand" auto parts store (Pep Boys, Western
Auto, Auto Zone, etc.) and buy the Bosch plugs at about $1.50 each. The Bosch platinums have been running about $2
each at these places....

>>which I assume your owner's manual says is a Bosch FR6DC<<

Not Exactly...The Volvo srvc literature (not owners manual) states that you have 2 options: either the Volvo kit, or use
Champion RC 7 GYC . That plug doesnt seem to be available here, but does indicate to use a 7 heat range....The plug
IPD sells for our 850 Turbo (as well as all 850s) is the FR7DC, keeping with the same heat range....Maybe in Europe,
Volvo recommends a 6 heat range, but not here for some reason. Does that mean much to the chagrin of plug makers it
really doesnt make a difference? I wonder. So that's the plug I'll buy...While IPD sells it for $1.85, I have a parts store
who will sell it for $1.00! I dont know why its so cheap, but as they say, dont look a gift horse in the mouth, or
something like that. Nobody's ever said they've had trouble with the basic Bosch copper plug. The platinum is another
story though...several have commented that it doesn work well in our turbo models. And as for the Champions, more
than a few folks have said theyve had big trouble with quality like porcelain braking, and so on. So Bosch basic
FR7DC it is.