Fuel efficiency: 10 mpg loss after service. What to check?

Nasher said:
Not really. Most turbos will run fine on 95 ron...
Click to expand...

Because that's what the manufacturer tuned them for. A turbo charged engine will have a far greater delta in peak power between 95RON and 99RON compared to a N/A engine.

A BMW S55 engine makes 40 horsepower less when ran on 95RON, I've witnessed it. The average N/A production engine is likely to see more like a 10 horsepower difference between the two fuels
Diagro said:
It doesn't. You also missed the point. I have an objection to his use of the word 'fact'.

Obviously gone over his head, and yours.
Click to expand...

Hasn't gone over my head at all. His opinion of V-power vs Tesco isn't fact, and neither is yours.

You say there's no difference. I have empirical evidence that says otherwise.
Ultimately what's best for one engine isn't best for the next, some will perform better on one fuel than another
 
Frozennova said:
Because that's what the manufacturer tuned them for. A turbo charged engine will have a far greater delta in peak power between 95RON and 99RON compared to a N/A engine.

A BMW S55 engine makes 40 horsepower less when ran on 95RON, I've witnessed it. The average N/A production engine is likely to see more like a 10 horsepower difference between the two fuels


Hasn't gone over my head at all. His opinion of V-power vs Tesco isn't fact, and neither is yours.

You say there's no difference. I have empirical evidence that says otherwise.
Ultimately what's best for one engine isn't best for the next, some will perform better on one fuel than another
Click to expand...

His opinion is not fact, but he physically wrote that it was a fact.
Hence my sarcastic "fact" reply. Which has gone over your head too.

Anyway, fancy providing this proof? The data sheets I've been privy to basically show the same fuel chemically. Obviously depends on batch too.
 
Diagro said:
His opinion is not fact, but he physically wrote that it was a fact.
Hence my sarcastic "fact" reply. Which has gone over your head too.
Click to expand...
Well, not wanting to be that guy, what he actually cited as a funny fact was that he only used Shell, not that others should only use Shell. Which may well be true, even if it's daft :p
 
I paid 143p for vpower, how much is tescos fuel? The other thing to consider is how out of your way you have to go, i.e. for me to fill up at tescos its an extra hour detour whereas shell is on the way home. So cheaper for me.
 
Fuel wars.

BP and Shell have spent a lot of time and money to get their additives right but let's not kid ourselves on they are all about profits.

The way I view it is. If your cars is worth a lot of money or is a performance vehicle or has complicated parts then run premium from shell or BP.

If it's not worth a lot of money and is a bog standard type of engine then run supermarket stuff.

I fill up with Costco premium when I can. Sometimes v power or ultimate. Sometimes asda. At the end of the day sometimes you need fuel and you go where its convenient.
 
Diagro said:
His opinion is not fact, but he physically wrote that it was a fact.
Hence my sarcastic "fact" reply. Which has gone over your head too.

Anyway, fancy providing this proof? The data sheets I've been privy to basically show the same fuel chemically. Obviously depends on batch too.
Click to expand...

There isn't anything I can post as proof, two Dyno graphs showing a 7hp difference means nothing, likewise for two datalogs showing a 1 degree difference in ignition advance. I can't post what I heard on det cans 2 years ago.

Either way the difference was negligible, as above a degree of ignition advance and less than 10hp difference.

Datasheets for fuels are vague too draw any kind of comparison
 
130 here to for supermarket premium atm :( Been running various cars on it for years though with no issues (turbos, NA, tuned)

Vpower is just to much even if it is better. Even when I get shell vouchers I just use their standard stuff.
 
Anyway, back to the OP - it's been a couple of years since I've been that far north, but there was a noticeable difference in MPG between going from Aberdeen to Edinburgh and then the reverse route, probably more down to the geographical topography and weather.

In the past I've also found my MPG to dip slightly just after changing the oil, but it usually returns after a few hundred miles.
 
Psycho Sonny said:
Fuel wars.

BP and Shell have spent a lot of time and money to get their additives right but let's not kid ourselves on they are all about profits.

The way I view it is. If your cars is worth a lot of money or is a performance vehicle or has complicated parts then run premium from shell or BP.

If it's not worth a lot of money and is a bog standard type of engine then run supermarket stuff.

I fill up with Costco premium when I can. Sometimes v power or ultimate. Sometimes asda. At the end of the day sometimes you need fuel and you go where its convenient.
Click to expand...
Costco is worse than momentum now
 
Frozennova said:
There isn't anything I can post as proof, two Dyno graphs showing a 7hp difference means nothing, likewise for two datalogs showing a 1 degree difference in ignition advance. I can't post what I heard on det cans 2 years ago.

Either way the difference was negligible, as above a degree of ignition advance and less than 10hp difference.

Datasheets for fuels are vague too draw any kind of comparison
Click to expand...
Those changes are also down to differing environmental variables
 
Diagro said:
Those changes are also down to differing environmental variables
Click to expand...

Potentially, a degree or two in ambient temperature is unlikely to make a difference.

If I feel enthusiastic enough at some point I'll throw the supercharged BRZ or the Turbo ND on the Dyno at work a do a proper back to back comparison
 
You must log in or register to reply here.
Back
Top Bottom