Just a quick note on the question of which spark plug is correct. The reason for some of the confusion is
                      due to the advances in plug technology that allow a given plug to cover a wider heat range. That is why
                      you see some plugs, like the champion heat range 7, becoming hard to find or out of production.
                      Champion 9's cover a lot of heat ranges that used require a lot of different plugs. Same for the same heat
                      range called out for the turbo and the non-turbo. Nowdays one plug can cover them both. The days of
                      "hot plugs" and "cold plugs" is pretty much history unless you're into some EXTREME applications.

                      --
                      Steve

                      Steve-
                      When the I5 motors first came out, they used a copper core plug with one ground electrode. Turbo or
                      no, same plug. Then they had some issues with the non-turbo cars fouling the plugs on a cold start. The
                      solution was a multi-electrode plug. At the same time, they went to a 'dual-platinum' plug for the turbo
                      engines. Volvo now has two distinct spark plugs for the 'white motor', depending on whether it is turbo
                      or normally aspirated. Same plug for 4/5/6 cylinders respectively. The correct plug is the one the
                      manufacturer specifies.

                      Dave the Volvo Tech
                      '99 V70R AWD, '93 854 GLT, '82 242 DL

                      The current Volvo spark plug listing is:
                      X40 I4 turbo- 272344 Double platinum
                      850/X70/S60 I5 turbo- 272313 Double platinum
                      S80 I6 turbo- 272367 Double platinum

                      850/X70/S60 I5 n/a 8642660 Tri-electrode
                      S80 I6 n/a 8642661 Tri-electrode

                      The turbos all use the same plug- the different part numbers are for different quantities in the package-
                      same thing on the n/a cars. Currently, the turbo plugs are made in UK, the n/a plugs in France.

                      Dave the Volvo Tech
                      '99 V70R AWD, '93 854 GLT, '82 242 DL

                      --
                      Dave the Volvo Tech

                      Problem is the original owners manuals and a lot of the aftermarket catalogs don't reflect that kind of
                      info. Single massive electrode plugs are what you get over the counter. For most apps they function fine.
                      The platinum and multi electrode are the way to go for sure if you want long plug life and that last ounce
                      of performance.

                      --
                      Steve

                      Do you have the part # for the multi-electro spark plugs? I wonder if Bosch makes one!

                      Chuck-
                      I'll check at work tomorrow and get the part #s for 5 and 6 cyl turbo and n/a applications. We use
                      OEM exclusively and other than the cold start flooding on cars that are started/shut off cold and the few
                      that need SW upgrades, see no problems with misfire or hard starting on any of these cars for the 30k
                      interval recommended on plugs.\

                      Dave the Volvo Tech
                      '99 V70R AWD, '93 854 GLT, '82 242 DL

                      --
                      Dave the Volvo Tech

                      What's wrong with the OEM plugs that Volvos engineers use, sold at Volvo dealers? They last at least
                      30K miles, starts the engine when cold/hot and does exactly what is was designed to do.
                      Aftermarket plugs won't improve anything despite the hype written in their advertising sometimes (like
                      better mileage/performance.....NOT possible).
                      Considering all the engineering that went into that engine, fuel and ignition systems, do you think that
                      they'd skimp on spark plugs for some odd reason?

                      I just ordered five NGK spark plugs for my S70. The part # is BKR6EKUB. They are dual ground
                      electrode plugs. They are recommended by NKG for 1999and current S70 model. Since my
                      experience with multi-electrode plugs in my five cylinder Audi is very favoriable over single electrode, I
                      will give it a try.