I'm probably going to be buying an S80 this weekend... used, not new. I was looking at the engine specs... 10+:1 compression ratio on the 2.8 twin turbo... I take it that means I'll have to run premium fuel, right?

Thanks,

Ben

:cat: Hi there henrysrodshop.

Review my postings and you'll see how much stuff is written about octane ratings on petrol and its use.

In a nutshell-use 98 octane petrol if you can buy it. Great starting, great performance, great economy regardless of whether or not you use your turbo. If the car is turbo-definitely use the highest octane available in your area.

Good luck with the purchase. Post pix too. :57: :)

Cheers :right:

No, the compression ratio of the twin turbo T6 is 8.5:1 someone is probably getting it mixed up with the 2.9 model, that is 10.3:1

Premiem fuel varies in octane rating depending on where you are.

The recommended Octane is 95, but the engine is designed to run on octane as low as 91.

Maybe I'm reading this info wrong... is the 2.9 a single turbo charged inline 6cyl w/approximately 195hp? Then the T6 is the 2.8 with twin turbo, inline 6cyl w/approx 270hp, right?

I thought I had read that the 2.9 was around 8.5:1 and the 2.8 was 10.5-ish:1...?

Ben

The 2.9 is not turbo it is NA

Well, we ended up buying a 2001 S80 T6 Executive model... it's very clean, 60k miles. It has a few cosmetic blemishes, but no dents that I could find, just a few rock chips, and a few tiny stains on the interior. Even the black coating on the doors around the windows is pretty much perfect (it's nicer than any of the other ten or so we looked at including mostly 2002's and 2003's!).

Anyways, I'll post a couple of photos later today once it's light out enough to take a picture! :)

Also, in reading the manual, it says the minimum octane is 87, but we're going to be certain to run at least 90 (mid-grade)... we should be safe with that... I think? Another question: can we run E85 in this? I've read that the octane rating is around 105, but it doesn't play nice with some hoses and seals...?

Ben

My 2000 S80 manual says 91 Octane. Your mid-grade 90 octane should be ok.

You are right. E85 has a 105 octane rating. However the fuel economy will probably be worse for non flexible fuel cars like our S80. E85 has less energy than gasoline for the same volume. However E85 may give a performance boost for turbo charged engines like the T6.

Use E85, if you want to race it around the track but I would not use it for prolonged normal driving.

You are also right about the E85 effects on seals.

If you run 100% E85 your O2 sensors will detect the extra oxygen and your ECU may spit out all sorts of emmissions and engine warning messages. Probably not good.

I think Minnesota has legislated E20 for sometime in the future which is ok for most of the modern cars on the road now. Then one would think it would be ok to blend about a quarter E85 with normal gasoline.

Looking forward to seeing those pictures.

I was looking through my manual last night, and noticed that the 2.8 is listed as 8.5:1 and the 2.9 is listed as 10.5:1 compression ratio, FYI.

I'll try to take some more photos this morning, but I have orders to re-organize the garage to make room beside the hot rod for the Volvo... ;)

Ben

Factor in that NZ probably uses RON metho of calculating octane rating and the US uses the RM/2 method.. I think 98 RON equates to 93 RM/2

I tend to get my premium from Citgo.. normally only because they are nearest and cheapest.. Viva Chavez hahah

i'm also new to forum and some question regarding fuel consumption.
the previous owner was using regular fuel which has 87 octane. i'm trying to put gold which is 91 octane. should i somehow clean the engine to get ride of scale? what do you suggest? should i clean the system?

Thanks in advance

:cat: Hi there kozak.

Don't put anything into your petrol to clean the engine. The additives in the petrol will do that job for you.

Volvo make it clear in the owners manual not to use additives. It could have something to do with the oxygen sensors.

This topic has been well covered over the past twelve months or so.

Cheers

As long as the fuel that you are using is from a reputable source, all the fuels have an additive in them, no need for any more to be added. use the 91, it is fine, kozak.

I always tend to go for the 93 octane from whatever gas station is cheapest... prices tend to vary not so much by brand but more by location than anything....
Its odd though, volvo claims dont use additives then companies like shell who make the vpower additive say its safe on oxygen sensors.. Probably better not to take the risk in that case.?

i think they mean don't use any outside additives. like a octane boost sort of additive. or a murphys oil. the oil companies formulate their additives for the masses of cars, not speciic models. so i don't think they would want to have a bunch of lawsuits on their heads, not like they don't have the money or anything.

Its true what your saying... Il have to read up on the fuel additives...
I know reading that i shouldnt use any oil additives but il have to ref my manual regarding fuel additives..
Reason I ask, someone gave me a new bottle of shell vpower fuel system cleaner.. its normalyl about 6 or 7 dollars for the bottle and its one time use so I was wondering if to go ahead and use it or not...

:cat: Hi there.

I don't wish to be negative-but if you've read everything in this forum about additives and are still worrying or trying to work out if you should use it or not,

go ahead and use it. The worst that could happen-you've already been told.

Good luck with your decision either way.

Cheers :right:

Nothing will probably happen if you did use it. Nothing being, your car won't die, and then, you are unlikely to notice any improvements either.

If you do use it, do it just before the service when the fuel filter is due to be changed. That way, the impurities (if any) will be discarded with the old fuel filter.

good call from poopbunny. this is not like russian roulette. a single bottle won't hurt.

According to the Manual, Volvo recommend premium (Octane 91) for Volvo S80. You can use Regular (87) but you wont get good gas mileage. I always fill it up with premium.

Do not use E85 in your car in any amount if your car does not have a flexi fuel engine, would you mix a bit diesel in your petrol as well?. The engine of a flexi fuel and the injection system has to be built for it, ie different injectors and hardened valve seats to name a few.