MPG drops like a stone

You only lose the loony 20-90 resume fun that can be had with big engines and an auto!

Reply to
Scott M
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Ah, you too have driven through the Fortune of War chicane heading to London.

Reply to
MrCheerful

Modern cruise controls seem reluctant to unleash all the horses on resume. My old DIY fitted vacuum unit would just whack the throttle open to maximum. Much more fun. ;-)

Tim

Reply to
Tim+

I found it useful for adhering to speed limits and maintaining steady speed on longish journeys.

The two things I miss most from the Mondeo to the Focus arew Cruise control and climate control.

I listen to the engine note, and select the most suitable gear.

Reply to
Gordon H

Me too.

Reply to
Gordon H

You get better fuel consumption by reading the road, especially in busy areas in the UK.

Driving on a motor way on a downhill section and seeing that the next 2 miles is all up hill the more sensible thing to do is increase speed by a small amount before getting to the uphill section. Having done 300 miles of motorway driving this weekend I noticed a few drivers 'causing problems' by dropping speed by 10/20 mph towards the top of a incline resulting in other traffic bunching up behind them and then attempting to change lanes to get past.

Reply to
alan_m

It happens that MrCheerful formulated :

As said, it works best with a manual which has lots of torque. If I need to slow down, its just a matter of pressing 'resume' to go back to the original speed, other than that I find I make extensive use of it, even when towing - the torque usually takes care of any hills.

Reply to
Harry Bloomfield

Peter Hill was thinking very hard :

I have three speedos - the analogue which lies, digital and GPS, bot of which are on the nose. I set my cruise by one of the latter.

Reply to
Harry Bloomfield

Graham J formulated the question :

So you are not really doing the 70 limit..

Reply to
Harry Bloomfield

Tim+ has brought this to us :

The pulses are very accurate, the only variation is that of tyre pressure and tyre wear.

Reply to
Harry Bloomfield

The pulses from gearbox are accurate.

Using all the tread, tyres wear about 14mm on a 630+mm dia - 2%.

The speedo calibration is the big issue. They set them to read fast so they can't be taken to court for speeding fines, court costs and taxi fares. Calibration is done on final test by feeding a fixed frequency pulse train to the speedo and adjusting a variable resistor.

Reply to
Peter Hill

Peter Hill expressed precisely :

2% is really not that much (1.4mph at 70), so little I would not be able to detect it comparing my GPS against my digital dash reading.

No variable resistor in my dash, but does it really need one? Modern instruments, like mine, use a stepper motor so the needle precisely registers the value they are told to deliver referenced to the zero stop. The few mph positive offset is deliberately programmed into the logic of the dash. That, due to the C&U regulations and manufacturers trying to remain on the safe side.

For emergency service use, they are quite capable of setting the offset to none, to provide an accurate value.

Reply to
Harry Bloomfield

Agreed, sound technique.

Reply to
Gordon H

And if your cruise speed is already 70MPH?

Reply to
Berty Blenkinsop

When I built my electrically powered racing (endurance) 'motorbike', I used an 'inductive sensor' drilled and tapped into the final drive to 'count' the teeth on the final drive gear. I then used a F to V converter and fed the output of that into a DVM module with said 'trimmer pot'.

I did all the wheel circumference / revs per mile > pulses / mile calculations and then fed the resultant frequency into my F/V converter and adjusted the pot to give me the predicted reading of volts as MPH. It turned out it could resolve the speed better than the Radar gun they were using (for our benefit as not all vehicles had speedos). ;-)

Cheers, T i m

Reply to
T i m

I don't have cruise control on this car, will have on my next, but the technique can be used at any decent speed.

Reply to
Gordon H

I've had it in the last two cars, both Audi's, but never used it or seen the need for it really.......

Reply to
tony sayer

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