Replace wires at approx 100k miles, with Bougicord (OEM)

The tensioner should be ok, but if you feel more comfortable replacing it, no issue there, other than cost.

Definitely replace the pulleys though.

If your car is a non-turbo, go with the Volvo 4 prong plugs (every 25-30 k miles) to prevent fouling and warm start issues. If turbo, good old copper cores are recommended by just about everyone.

Bosch for all other electricals, where applicable is always a good choice

eeuroparts.com or fcpgroton.com both have excellent prices, but I would have to agree with another reader, eeuroparts will probably be faster shipping for you.

BB
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1998 V 70 BASE

As for the plug wires, most any decent brand will do and you don't need to be concerned about resistance. Of course check the condition of the existing and replace if you have any doubts.

Same thing with the plugs. I like the basic Bosch platinums, very durable plug.

I'd definitely shorten the specified air filter interval. I change mine every 10k.

Bill,

I have no idea of the answers to your question, but I'll say this. If you don't know anything about the prior maint you can assume its hasn't been done lately. 850's are picky about plugs, rotor and dist. cap. About 25-30k miles is all for them. So get those too. And you might want to check www.eeuroparts.com - they give free shipping on orders over $35 and I usually have the parts the next day as they usual ship via FedEx. Although fcpgroton is good too.

As for wires and timing belt - miles and time need to be considered. If you have any question about if go for the change. And there are those that replace pulleys every timing belt change as long as they are in there.

And don't forget flame trap (if non-turbo), oil & air filters! And a few of the crush washers for the oil drain plug while you are ordering things are handy to have.

Enjoy!