What fuel type would make the ST more responsive?

chip pan oil maybe lol

Nowt that can really make a difference

Higher octane fuel is really just for Ferrari's and Aston's!

I use a special light weight fuel, called just above the red ! faster than with a full tank.
Think BioFuel makes more BHP.
Stick with VPower, engine likes it a lot, mine does, sometimes in fact now it has standard in and I can't tell any difference, most of my fill-ups are VPower for the better cleaning agents.

If you're using standard, some fuel system cleaner every six months will do a good job of keeping the fuel system tip-top.

Bit cheaper than filling with v-power. But I definitely agree that Shell with their 95RON is better stuff.

Just use a good fuel like Shell or BP, just avoid supermarket rubbish! No point wasteing money on 97-98 ron fuel the car is set up to run on normal unleaded.

would recommend shell or bp. i can tell the difference when i fill at tesco then go to shell. v-power is good but unless rolling road i jus use standard shell unleaded...

are we talking the bp ultimate?? or normal bp fuel

Has to be normal BP. The ultimate is a rip off.

The ST was set up mapped to run on BP 95RON. Some other 95RONs are just as good ie. other branded fuels like Shell, others are worse ie. cheap supermarket fuels. Using super unleaded is a waste of time and money, as the ECU can't adapt to it. It just sends more unburnt fuel into the cat and coke it up.

Everyone always talks about good branded fuels, shell, BP etc and bad supermarket fuels.

The rather convenient garage at the end of my road is Texaco, I would say this counts as a branded fuel but occasionally I'll stick some in from Tescos. Anyway the fuel at Tesco says 95RON as does the Texaco stuff so if that's a standard what's wrong with using the supermarket stuff? - I've never noticed any difference with the way car behaves.

I am informed that the ECU can adapt which is why the car will safely run on 95 or even 102 BP special.

As I believe, it's the supermarkets that buy, shall we say the offcuts from fuel production. Even fuel has a shelf life and needs to be stored properly and should have additives to protect your car.

This wasn't really a problem with four star, as the lead slicked up the engine and the shelf life was a bit longer.

Sometimes it's worth paying a little extra for the 95RON from Shell etc as they do look after their product. Saying that my local Shell is a penny cheaper than Sainsbury's at the moment!

So if it's had a remap is it worth putting slightly better fuel in?

yes for the cleaning agents.

Probably better to get an efficient remap that makes the best of 95RON fuel

You don't really want to be paying for Super if you don't have to

i run mine on v-power or BP

never supermarket fuel.

Dal

Yeah il agree morrisons fuel seems alright. Put tesco's and asda's fuel in before but never again, seemed to idle iratically and felt like my car had less power.

ive always used v-power

1) cleaner for the engine

2) it smells fine since my car has full milltek decat, !!!

ive never used supermarket fuel and would rather stutter home to get better fuel than put in the rubbish from asda etc.

Well I use supermarket fuel and was doing 10mph and pulled away in 4th...think I can hear the noise people wear mentioning...pinging/pinking??

I have always used Texaco's High Octane fuel, am I doing any damage or benefit to my car?

Wow old topic

No benefit from it
Some find it makes the car run a bit rich

Yes sorry about digging it up, didn't want to start up a new thread if there was already one going.

Should I switch to normal fuel or what? I've been using high octane since I bought the car and it's at 17k now on a 57 plate. I always thought using the high octane would keep the engine cleaner and what not? I've not done damage over the time have I?

Won't damage it just unnessecary

good to use it now and again for sure.

So as I have the money it will benefit by continuing, as it will keep the engine cleaner etc?

And I thought it adds 3-4 BHP supposedly?

yes and maybe on a rolling road.

Okay I think I'll stick with the High Octane, I get a couple or three more MPG too.

I filled up on the way to FITP with Tesco High octane and while driving up thought something was wrong with the car. Filled up on the way back with normal Shell (what I normally use) and the car felt more responsive, and slightly quicker. This could have been because the ecu was used to running on Shell mind...

Sainsburies = Shell
Tesco/Asda = Esso/BP (region specific)
Morrisons = Texaco

But so you all know, no matter who supplies the contract, whoever the name on the tanker, the actual petrol going into these tankers comes from exactly the same central based refinery in the UK, made to same standard (EN 228).

The only difference is the adatives they add to the fuel. The increase in ron is based on increased levels of methonol in the additive.

So, heres an argument starter - do you still think any one companys fuel is any better than any others? or is it mind over matter?

Some are better and its been tested and proven

you stick alcohol into your fuel your going to get a better bang, but that doesn't mean its "better"

Where do I get this alcohol from? Anything? Just a bit of good old Jackie D

TBH I just fill up whereevers cheapest, never had any problems, I don't think the vast majority of the population even worry about it, just go to the nearest pump

if your running on track days then i can see the need for hi octane fuels but for normal day to day running on an st, standard fuel is fine. i only put it in once every 4-5 fillups for a clean and thats only half a tank. dont care where it is from its just usually the cheapest i go to

I just use regualr shell all the time as its my nearest petrol garage and is normally cheaper than other places

I used to always use BP but they got to greedy and charged upto 5p more a litre than shell!

I always use the cheepest for everyday driving. When im going on a rolling road i run it down and use the good stuff for a week or so prior

Is that for the added 3-4 BHP that you supposedly get? Have you ever tested if you do actually get the added BHP?

I think you may get 1-2bhp if you're lucky!!

its only really in subaru's and that sort of performance car that benefit from it really. Think they did a test on fifth gear with it on normal cars then going upwards to more high performance orientated ones

Somebody earlier in this thread said that the 'basic' ecu on the Fiesta ST can't adapt to higher RON fuels. This is in correct, the engine management software for the ST includes active knock and will advance spark timing to a predetermined knock limit. Therefore if you put a higher RON fuel it will give you more spark and theoretically more power.

No that was Dave that said it....it can't adapt

correct it has adaptive tables that can repopulate accordingly, may not notice anything on the road but maybe on a rolling road, filled my half tank of VPower with standard on top other day and runs just fine on the mix

Knock control just manages "pinking" conditions, nothing to do with the MAP.

The software doesn't have 'adaptive maps' and they can not re-populate themselves, but it will advance spark timing up to predetermined knock limits. Knock control is basically just a combustion quality monitor, however the ST only has one knock sensor so it's not the greatest system in the world. But the higher the RON rating of the fuel the better the combustion stablility and therefore more power can be produced within the limits by running more aggressive ignition timing.

I undertand Mountune Maps can.