General Multijet fuel consumption / economy

[Geddes]

That is interesting. Can you state the normal/fully-laden/eco pressures, please?

32/34/35 psi

Tyres are the exact same 155/80/R13 Conti Eco3's that the Panda came with,though the Spark is some 100kg heavier.

If he feels like it a copper will go over everything that takes his fancy. I had a run in with them once when driving a Mini on flat hydro suspension to the garage to get it pumped up. Despite having the Haynes manual with me saying it was fine to drive on flat suspension he argued the toss about everything, including the location of the garage I was driving to.
Got a prohibition notice in the end.

 

[Most Easterly Pandas]

Wow, that's completely nonsensical.

What if you've put on bigger wheels and switched to tyres that have a significantly lower profile? Running at stock pressures on a setup like that could be dangerous.

Besides, who's going to check your tyre pressures?

Police can and do check pressures.

There is no such thing as stock pressures, there are correct pressures for all Tyres depending upon tyre size and the weight they're carrying

However what Geddes has said is indeed interesting.

 

[trackdayqueen]

There is no such thing as stock pressures, there are correct pressures for all Tyres depending upon tyre size and the weight they're carrying

However what Geddes has said is indeed interesting.

Exactly, so as long as your tyre pressures are in range of the tyre you aren't going to have a problem. If a copper is checking your tyre pressures then you have seriously upset them. Have never in 22 years of driving and getting stopped hundreds of time in my youth had my tyre pressures checked.

 

[Geddes]

Exactly, so as long as your tyre pressures are in range of the tyre you aren't going to have a problem. If a copper is checking your tyre pressures then you have seriously upset them.

I doubt you'll have a problem unless you're driving round on obviously near-flat tyres in which case you'll get a tug.

You do hear things about insurance and tyre pressures, but probably they'd have to show the state of your tyres contributed to an accident.

 

[Bri]

After 30 odd years being a vehicle engineer and a recovery driver serving the motorways around the northwest of england etc ,ive seen lots of traffic accidents and the police doing spot checks ,checking tyres and pressures .And also being a "Expert witness" on numerous occasions in legal cases.And insurance companies trying ways to aportion the blame for claims.

 

[Bri]

Cumbria Police is being joined by Eddie Stobart to launch a month long campaign urging drivers to check their tyres are safe and legal.

Sadly each year, dozens of people are killed and hundreds are seriously injured across the UK as a result of collisions caused by illegal, defective or under-inflated tyres.

 

[SpartanX]

Bit of a thread hi-jack - no problem. To return to the original subject(ish)

Well, yes and no. The power curve dips quite severely at that point, but it's nothing like the fuel cut at 5000rpm. That one stops you good.

But there's absolutely no reason to ever get above 4000rpm, a higher gear will put you in a part of the power curve with much more on tap.

Well, maybe this a subjective thing or varies from car to car but I can determine nothing severe at 4k revs; to me, it seems to fall away gradually from about 3,500 to 4,800. In reality, I noticed that when I was 'hustling' in this way I was actually changing gear between 3.5k to 4k. In deference to your remarks about the 'redline', I would like to update the first post accordingly but it'll just confuse the thread.

Anyway, it occurred to me that the real reason that I'm probably seeing this increase in mpg by revving higher before changing up is because - on my relatively short journey - it means I'm just getting the engine up to its most efficient operating temperature sooner.

 

[Bri]

I have noticed that if i use branded fuel (shell etc) the fuel lasts longer? and the car runs better .i think some supermarket fuel varies quite a lot.But last winter with using the heater and lights a lot the fuel ecconmy was dreadful.This is why i mentioned about running with lights/heater on affects fuel ecconomy.And in the cold weather it used more fuel until the engine gets to working temp.

 

[SpartanX]

The 'winter diesel' (with additives to stop the fuel going waxy) could also be another factor for poor mpg that you describe.

My observations have all been made relatively recently and I think that, at least as far as the idea that mpg can improve with higher revving is concerned, all I have really noticed is that warm engines produce better mpg figures, i.e nothing that wasn't already known. I guess this driving style would just help diesel engines to get up to temperature quicker but once there, it would undoubtedly have a negative impact.

 

[Wh05apk]

I think there may be something in holding onto the gears, I have read this before, by revving harder, you get the car up to the most efficient part of the rev range quicker, so if you can accelerate harder for a few seconds, then straight to top, it might be better than "labouring" through the gears at low revs for 20-30 seconds?