91 or 98 petrol

http://www.ford.co.nz/cars/the-all-new-focus/specifications/fuel

Ford suggest 95-98.

My missus has a Caldina GT-T and if she puts in 98 without telling me,i can tell straight away if its 96 or 98,heaps more grunt.

Same as mine, it will run 91, but goes better and further on 95

Recommended minimum octane rating for 1ZZ and 1AZ engines is 95.

Oh.just to be anal. there's no such thing as 96 at the pump anymore and hasn't been for many years:)

you lot all need to read up about octanes ratings. seriously, some people are spouting garbage.

tell us what you think then . mr know it all

i run my turbo'd car on 98 purely for the fact that i like my pistons INSIDE the block

I put 91 in my turbo CRD Jeep once, ran really well.for a while, thank goodness for Sukimoto! Wife's SAAB runs really well on 95, pinks like hell on 91. The 115 on the boat likes 91 though.

Mine goes well on LPG

I run all mine on 98, even the motor mower.

everyday high performance car-great economy.
high octane performance in race car.
good power from tow car.
any older gas left goes into the mower.
so why not!

Use 91 in the motorcycle as that's the minimun asked for. Trying 95 in the car at the moment, might need to change the timing though.

i've always used 95 or 98 on the turbo. and she loves me for it.=D

Then how can you tell if you haven't tried it on 95!

Run the (modern Mini S) on 98.Older road/race car with cast iron engine also on 98, but with an occasional splash of leaded race gas.

Race gas doesn't make it go any quicker, but gives me peace of mind regarding valve seat recession, given that the engine is only ever driven flat out.When the crap unleaded first came out, the car was pinking within 300m of the petrol station.

Modern cars with computers probably have adjustable timing to suit the fuel.

We run the Jag on a 98/Avgas mix. Pinks like a b*stard on 98 alone for some reason. Mind you it is fairly hot for an old engine.

Lotus runs on 98 exclusively and Pug runs on 95/98

Most likely YES!

I will take a stab and say this vehicle is some kind of direct injection vehicle.

Direct injection vehicles are often capable of phenomenal efficiency. They do this by utilising phenomenal control over the combustion process and control aspects like knock control to within a hairs breath. For someone to try and run such a sophisticated engine on low grade fuel is like trying to adjust a switch watch with a sledge hammer.

(I will post below more on how it works in case anyone is interested)

Now that said, generally, you can get away with the odd tank of 95 in these cars without damaging the engine so don't panic if you run out in a town that dosn't have it. Mostly your economy just goes out the window. To quote VW's a Golf FSI will typically get itself into lean burn FSI mode about 20% of the time if you are running 95 vs about 60% of the time on 98.

If you run 91 in direct injection cars the vehicle will still go (Which is actually a shame, it would be better in a lot of ways if it didn't) but you start damaging the engine with residue from the incomplete combustion. Unlike your Morris Minor when it became "carboned up" there is usually no inexpensive way of fixing this damage.

This is where the majority (but not all) of problems seem to stem from with the likes of the Mitsubishi GDI engines. I have a suspicion that Mitsubishi drivers (and Toyota drivers) are particularly bad at not running the correct fuel. This could likely be why the Volvo's that run Mitsubishi GDI engines are still statistically about the most reliable proper cars of that era you can buy.

Modern direct injection is usually a great thing, people just have to follow manufacturers instructions instead of packing a sad when it breaks.

FSI Technology explained (As promised above)

In a normal car the fuel is injected into the engine as the piston is on the way up, increasing the pressure in the combustion chamber chamber as it goes. Now, if you pressurise a fuel/air mix too much it will actually ignite all by itself, thats what causes "pre-ignition" or "knock". Which is basically fuel igniting before the piston is at the top of the stroke. So all that energy has no where to go and causes damage instead of dissipating by pushing the piston down. (technically you can actually get away with igniting it a little early under certain conditions but lets not complicate things)

Higher octane fuel burns slower and is harder to ignite by pressure alone. So in a traditional engine you can have a higher compression ratio and start intentionally igniting the fuel earlier. This of course makes for more efficient running (Think nice long push down on a bicycle pedal as opposed to smaking it with a hammer at the top of the stroke).Even though the same amount of energy is contained in a litre of 91 as a litre of 98 with a correctly tuned engine (or one that can adjust itself enough) you will be able to put more of that energy to use driving the vehicle.

So. what about Fuel Sratified Direct injection!

Well that takes the control over the combustion process to a whole new level.

Firstly, instead of putting the fuel in as the piston rises to the top the fuel goes in really quickly just before its ignited with the spark plug. This gives you a huge advantage in the war against high compression for efficiency vs pre-ignition. Basically pre-ignition can hardly happen at all so you can wind up your compression ratio's significantly.

Secondly. there is so much control with this injection that you can not only direct where abouts in the combustion chamber you want the fuel, you can actually set up certain area's of the combustion chamber to run a richer mixture than others.

Traditionally if you want to run a super lean mixture you have real trouble getting it to ignite as and when you want it to if it even ignites at all.With FSI you get around this by making the area around the spark plug a fairly rich mixture with the outlying area's being leaner. The burn of course starts in the rich area and then this large flame is able to ignite the leaner portion.

SO. with a system that clever. it should be pretty darn easy to see why running it on the very high octane fuel its designed for is so important.

This technology was also part of what made the MK5 Golf such a revolutionary vehicle in terms of economy. The Golf that came before it and the offerings of its competitors were left in the dust once you put this technology together with 6 gears and no torque converter.

Good on ya thejazzpianoma, punters will lap that up and go out and buy a Direct Injection VW tomorrow. ;-)

And so they should!

(I actually edited it to put a wee bit more VW plug in there at the end for you!)

Seriously, though VW's Direct Injection is one of the best in the business. Its reliable, and if you need a replacement fuel pump they are available for a sensible price (although I am yet to come accross someone who has had to replace one).

You should have seen the abuse I used to get a few years ago when I told people I could get under 5l/100km on a trip out of a 2.0 car that wasn't a manual. and that same car could do 0-100 in under 9 seconds. That was about 7 years ago, but more people are starting to get it now though that they have driven some of this technology for themselves.

I'm not going to take your word for it (low credibility). I have no interest in investigating on my own either.

LMAO!
This speaks volumes.
Have a lovely day.

91 fuel has a very short shelf life,also.Use it or lose it!

My 1988 CRX throws a check engine light at anything less than 95.