Speed Awareness Course this PM - What to expect?

[anonymous-user]

rainmakerraw said:

Assuming constant throttle though for the entire distance travelled in both gears, right? From a cursory glance, your map shows a difference of about 0.2 milliseconds worth of fuel injected at any particular stage/level of inlet vacuum at the revs under discussion. That's 0.2 milliseconds of extra fuel. How much does 0.2 milliseconds extra fuel spray kill MPG on an average real world urban run? I'll wager not much as I never see any appreciable real world difference and again it would surely rely on constant throttle in both instances. Since third means you can be off the throttle completely, and thus using no fuel, for a lot more of the time for any given A to B section of road, it surely averages out? It's literally the difference between near constant throttle in 4th for the duration, or pulse and glide in a lower gear. As I said I find no real world difference between the two give or take a fraction of a MPG, and it's more drivable and arguably safer real world. So, as with anything you pays your money and takes your choice.

As I said if I've been taught wrong and my real world observations are wrong I'm 100% happy to change my mind. It's how we learn. But so far the assumptions seem to be that both conditions are equal in application, when they're not. At your own admission you use no fuel when you're on the over run on most cars, which is entirely my point. The higher gear requires more constant throttle input and loses those extra revs, leaving you no room for 'play' in being off throttle on approach to a hazard, necessitating a down change anyway. I just don't find it makes any real world difference worth bothering about.

the watering down begins.

Surely you can see that to achieve 30 in 3rd requires more throttle than if you're in 4th or 5th?

Surely you'd agree that engine braking would be greater when you lift off the throttle in a lower gear - thus requiring yet more throttle to get back up to 30?

[Countdown]

bmw535i said:

You just went out for an hour as a result of this thread!! Blimey.

Not sure how you figure you'd use the throttle less in third - surely you need to use more throttle and revs to achieve the same speed in a lower gear?

Accelerating from 20mph in 4th requires more throttle than accelerating in 3rd from the same speed, because the engine is producing more torque. Or, to put it another way, you'll need to be on the throttle harder for longer. This is all dependent upon your engine's torque curve.

[anonymous-user]

rainmakerraw said:

Assuming constant throttle though for the entire distance travelled in both gears, right? From a cursory glance, your map shows a difference of about 0.2 milliseconds worth of fuel injected at any particular stage/level of inlet vacuum at the revs under discussion. That's 0.2 milliseconds of extra fuel. How much does 0.2 milliseconds extra fuel spray kill MPG on an average real world urban run? I'll wager not much as I never see any appreciable real world difference and again it would surely rely on constant throttle in both instances. Since third means you can be off the throttle completely, and thus using no fuel, for a lot more of the time for any given A to B section of road, it surely averages out? It's literally the difference between near constant throttle in 4th for the duration, or pulse and glide in a lower gear. As I said I find no real world difference between the two give or take a fraction of a MPG, and it's more drivable and arguably safer real world. So, as with anything you pays your money and takes your choice.

As I said if I've been taught wrong and my real world observations are wrong I'm 100% happy to change my mind. It's how we learn. But so far the assumptions seem to be that both conditions are equal in application, when they're not. At your own admission you use no fuel when you're on the over run on most cars, which is entirely my point. The higher gear requires more constant throttle input and loses those extra revs, leaving you no room for 'play' in being off throttle on approach to a hazard, necessitating a down change anyway. I just don't find it makes any real world difference worth bothering about.

OK, just sussed out what you are suggesting.

You are one of these idiots who cant drive at a constant speed in the flow of traffic, but are constantly accelerating and then slowing down. You clearly don't realise this causes the people behind you to get frustrated, leading to risky overtakes. It's also terrible for fuel economy, because you use more fuel accelerating back up to speed than you save coasting down.

Whenever you accelerate, you are not only using fuel based on your base fuel map, you are also introducing transient fuelling into the equation, which adds more fuel on top of the base map. It does the same job as a pump jet on a carburettor. Terrible for fuel economy.

[anonymous-user]

rainmakerraw said:

Assuming constant throttle though for the entire distance travelled in both gears, right? From a cursory glance, your map shows a difference of about 0.2 milliseconds worth of fuel injected at any particular stage/level of inlet vacuum at the revs under discussion. That's 0.2 milliseconds of extra fuel. How much does 0.2 milliseconds extra fuel spray kill MPG on an average real world urban run? I'll wager not much .

on my engine it would use 206cc/mile more using 3rd rather than 4th at 30mph with a 0.2m/s change in fuel flow.

That's the equivalent of losing 12.36 miles from a 60 litre fuel tank fill.

[anonymous-user]

Countdown said:

ccelerating from 20mph in 4th requires more throttle than accelerating in 3rd from the same speed, because the engine is producing more torque. Or, to put it another way, you'll need to be on the throttle harder for longer. This is all dependent upon your engine's torque curve.

When you reach 30, you'd change up in order to use less throttle.

[anonymous-user]

jsf said:

OK, just sussed out what you are suggesting.

You are one of these idiots who cant drive at a constant speed in the flow of traffic, but are constantly accelerating and then slowing down. You clearly don't realise this causes the people behind you to get frustrated, leading to risky overtakes. It's also terrible for fuel economy, because you use more fuel accelerating back up to speed than you save coasting down.

Whenever you accelerate, you are not only using fuel based on your base fuel map, you are also introducing transient fuelling into the equation, which adds more fuel on top of the base map. It does the same job as a pump jet on a carburettor. Terrible for fuel economy.

It is terribly annoying when people can't read the situation and maintain as constant as speed as possible.

He'll be off out again for a cruise tonight to try and convince me

[Johnniem]

I did the speed awareness course about 18 months ago and found it to be much less dictatorial and condescending than I thought it would be. We were treated like adults and not preached to at all. It turned out that all attendees were the 'Tower Bridge club'. Everyone had been caught doing in excess of 20 mph on Tower Bridge. Who'd a thunk?! In fact, many of the London crossings are now 20 mph although only a few have cameras, perhaps only Tower Bridge. It's a camera so you will get ticketed, no matter what time of day or night you commit the heinous crime! Mine was at 05.00 am, on my way to Smithfield for the annual Christmas meat buying fest. Others on the course were far earlier than that.

[anonymous-user]

jsf said:

rainmakerraw said:

Assuming constant throttle though for the entire distance travelled in both gears, right? From a cursory glance, your map shows a difference of about 0.2 milliseconds worth of fuel injected at any particular stage/level of inlet vacuum at the revs under discussion. That's 0.2 milliseconds of extra fuel. How much does 0.2 milliseconds extra fuel spray kill MPG on an average real world urban run? I'll wager not much as I never see any appreciable real world difference and again it would surely rely on constant throttle in both instances. Since third means you can be off the throttle completely, and thus using no fuel, for a lot more of the time for any given A to B section of road, it surely averages out? It's literally the difference between near constant throttle in 4th for the duration, or pulse and glide in a lower gear. As I said I find no real world difference between the two give or take a fraction of a MPG, and it's more drivable and arguably safer real world. So, as with anything you pays your money and takes your choice.

As I said if I've been taught wrong and my real world observations are wrong I'm 100% happy to change my mind. It's how we learn. But so far the assumptions seem to be that both conditions are equal in application, when they're not. At your own admission you use no fuel when you're on the over run on most cars, which is entirely my point. The higher gear requires more constant throttle input and loses those extra revs, leaving you no room for 'play' in being off throttle on approach to a hazard, necessitating a down change anyway. I just don't find it makes any real world difference worth bothering about.

OK, just sussed out what you are suggesting.

You are one of these idiots who cant drive at a constant speed in the flow of traffic, but are constantly accelerating and then slowing down. You clearly don't realise this causes the people behind you to get frustrated, leading to risky overtakes. It's also terrible for fuel economy, because you use more fuel accelerating back up to speed than you save coasting down.

Whenever you accelerate, you are not only using fuel based on your base fuel map, you are also introducing transient fuelling into the equation, which adds more fuel on top of the base map. It does the same job as a pump jet on a carburettor. Terrible for fuel economy.

I've also been out and done some research. I find my 530D auto, is in 5th at 30mph whilst the wife's 350SLK is in 5th or 6th. Both cars are quite happy in those gears on a constant, light, throttle. The instantaneous fuel consumption is indicated as being slightly worse if you hold them in 3rd gear, though it's hard to do it for long because they both go back to auto and change up a couple of gears quite quickly.

Even my Caterham R400D is quite happy in 4th at 30mph, though it is a 6 speed with ridiculously close ratios so it doesn't really count.

[Mr Taxpayer]

Given that the aim of the course is to improve you as a driver, attendance should qualify you for an insurance discount. Unless you put yourself forward for IAM training, or aquire further licences, no one undertakes any further training after passing their test.

In the safety hierarchy of controls "training" is always above "punishment".

[BertBert]

But insurance discount, based on what? What you should be paying, given you would otherwise have had a speeding conviction?

[Mr Taxpayer]

BertBert said:

But insurance discount, based on what? What you should be paying, given you would otherwise have had a speeding conviction?

Granted Bert, at present the only means to get on the course is to be coerced into it on threat of conviction. However, if the data shows that people who have attended these courses, are less likely to have a further conviction or be involved in an accident, then surely they should have a premium reduction?

I work as a system safety engineer and I've attended a Speed Awareness Course (35 in a 30). From a system safety perspective if you improve the training of the system operators, the system becomes safer. If they are safer the risk is lower, because the probability of a accident occurring reduces, and/or the severity is lower. Pilots do continuity training, so do train drivers and now bus and truck drivers. Big firms that have driver improvement training have demonstrably lower collision rates.

[BertBert]

Aha, I take your paltry one speed awareness course and trump it with my two courses

Yes of course, training in a skill will (everything else being equal) result in improved skills. I have no idea if there are any statistics on risk based around drivers who have had speed awareness courses against a control group. A quick google says no on first looking.

Admiral might have some as they ask about courses. But they aren't telling. Perhaps we could crowdsource Admiral's stats. If loads of people each get three quotes from Admiral (no points, 3 points for and SP30, a SAC) we could compare the quotes!

Bert

[anonymous-user]

Mr Taxpayer said:

BertBert said:

But insurance discount, based on what? What you should be paying, given you would otherwise have had a speeding conviction?

Granted Bert, at present the only means to get on the course is to be coerced into it on threat of conviction. However, if the data shows that people who have attended these courses, are less likely to have a further conviction or be involved in an accident, then surely they should have a premium reduction?

I work as a system safety engineer and I've attended a Speed Awareness Course (35 in a 30). From a system safety perspective if you improve the training of the system operators, the system becomes safer. If they are safer the risk is lower, because the probability of a accident occurring reduces, and/or the severity is lower. Pilots do continuity training, so do train drivers and now bus and truck drivers. Big firms that have driver improvement training have demonstrably lower collision rates.

Missing the point surely? One is sent on a course to redress a perceived weakness which, arguably, those who don't get sent on the courses don't have.

Why reward someone for needed remedial training?

[Dr Jekyll]

REALIST123 said:

Missing the point surely? One is sent on a course to redress a perceived weakness which, arguably, those who don't get sent on the courses don't have.

Why reward someone for needed remedial training?

It isn't a question of rewarding them, simply that insurance premiums should reflect risk. If people with criminal records tended to have fewer claims then their premiums would quite rightly be lower.

[BertBert]

So what group are the group of SAC attendees a lower risk than?

[exelero]

bmw535i said:

REALIST123 said:

He might be serious but he's not making any sense. A long time since I read such rubbish.

Really?
https://www.youtube.com/watch?v=soJea7xEt-8



My car at 30 MPH in 3rd gear is at 2000rpm exactly and I can travel at 30 with a really gentle touch of the throttle and some times just using the wheels (engine brake) to motion the engine.
A lot of you missed that apart from the engine and fuel there is a gearbox and due to the gearing 4th gear has less torque than 3rd.

But never mind no one is going to change his opinion anyway. So just stick in in 5th and off you go. Surely that's more economical than going through gears isn't it? Especially because your engine rpm will be exactly 0

Edited by exelero on Saturday 6th May 00:19

[anonymous-user]

exelero said:

Really?
https://www.youtube.com/watch?v=soJea7xEt-8



My car at 30 MPH in 3rd gear is at 2000rpm exactly and I can travel at 30 with a really gentle touch of the throttle and some times just using the wheels (engine brake) to motion the engine.
A lot of you missed that apart from the engine and fuel there is a gearbox and due to the gearing 4th gear has less torque than 3rd.

But never mind no one is going to change his opinion anyway. So just stick in in 5th and off you go. Surely that's more economical than going through gears isn't it? Especially because your engine rpm will be exactly 0

Edited by exelero on Saturday 6th May 00:19

Perhaps you missed the bit where we have talked about every car being different?

Is the car you're talking about a diesel?

Edited by anonymous-user on Saturday 6th May 00:40

[exelero]

Petrol, 1.6


ETA: If I use the 4th for 30mph the engine doesn't even sound right like is struggling

Edited by exelero on Saturday 6th May 00:44

[anonymous-user]

exelero said:

Petrol, 1.6


ETA: If I use the 4th for 30mph the engine doesn't even sound right like is struggling

Edited by exelero on Saturday 6th May 00:44

I see