Hi
Just looking at the figures for the new Accord in the Road Tests section, and noticed that while the 2.0SE does 0-60 in 8.7s, 137mph, 38.2mpg + 176g/km, the Sport does 8.9s, 135mph, 35.2mpg + 190g/km.
Given that the Sport only differs from the SE in having "Electro-hydraulic power steering; cruise control; 16in alloy wheels; front fog lights; technical metal trim inserts; no sunroof", are the differences in performance and especially economy to be expected? Is it the power steering that's doing the damage?
regards
John
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It's probably the larger wheels leading to worse aerodynamics and more rolling resistance, although the electric power steering is probably taking some power from the engine - though it's unlikely to be this extent. Shorter gearing (although the 0-60 suggests otherwise) is also an outside possibility.
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the electric power steering is probably taking some power from the engine .....
How? The engine isn't driving the power steering pump - it will be done via an electric motor powered by the battery.
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The engine is driving the alternator which is supplying the power to the steering or it is charging the battery or both. The energy has to be coming from somewhere and only source of it in the car is the engine IMHO. These strange people who drive their cars around all the time with the lights on(Volvo, BMW, Baseball hat brigade etc)are probably losing 1 or 2 mpg on this.
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On a Volvo, you cannot switch the lights off.
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On a Volvo, you cannot switch the lights off.
You can if you pull out the day running light relay or fuse. At least that's how you put the day running lights out on a Saab.
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Would that do any damage to the car? Would it vold my insurance? I thought about doing that but did not because I was worried about these issues.
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Mate of mine that used to work for a Saab dealership said it was common practice to ask the customer if they wanted the day running lights on or off when purchasing a new car from them. Most customers went for the \"off\" mode as they didn\'t want to get mistaken for Volvo drivers!! As for insurance issues, I have no idea where you would stand. One would hope that as it isn\'t a legal requirement to use day running lights in the uk, then why should they worry?
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"On a Volvo, you cannot switch the lights off."
You can switch the lights off on most Volvos without removing fuses. Those who wish to do so should check the handbook for how.
The problem I had with that is that the dash light stayed on which meant that I sometimes forgot about the headlights in poor light.
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The engine is driving the alternator which is supplying the power to the steering or it is charging the battery or both. The energy has to be coming from somewhere and only source of it in the car is the engine IMHO.
True - the engine is the source for the energy, but IMO you would be driving the alternator with the engine's power in all cases even if you didn't have any other electrical outputs other than keeping the battery charged. When you have a load on your battery it will get charged *more* by the alternator but that in turn doesn't put a extra load on the engine - as the engine would be driving the alternator anyway - hence same mpg regardless of load on battery (or thats *my* theory at least).
Chad.R
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Many cars that I have driven have done the following which in turn leads me to a conclusion:
If the car is idling thenI put the rear demisters on, the revs rise, only slightly, but they do. Now surely this means an extra load on the alternator and in turn the engine, thus revs rise. This in my experience leads to more mpg.
Both those Honda's probably have the same engine so differences probably come from wheels/tyres and weight. Those gizmos will not probably affect the performance but will increase the mpg slightly.
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Roscopervis I agree with your statements until you say that revs rise so "leads to more mpg". I think you mean rpm rises means more fuel burned and so fewer miles to the gallon? I hold to my view that the engine is the source of ALL energy consumed by the car and the more that is used (lights, windows, heated seats etc) the more fuel the engine has to burn to produce it. If some of it comes from the battery even that has to be recharged, by the alternator and driven by the engine.
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Oops yes thats what i meant! Less mpg would be the result, not more.
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Roscopervis, AS,
I agree, at idle the revs will rise when a load is put on the battery. I think the alternator doesn't charge the battery at idle (or at least not fully) therefore the rise in revs to compensate.
However, if you're cruising say with 2K rpm the alternator should be capable of charging the battery at that engine speed without putting any *extra* load on the engine.
Again, I re-iterate that this is *my* theory. It would be nice if someone techie literate could give us a full blown answer either way.
Chad.R
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Chad,
No, in short! The explanation is a bit complicated, but.....
Yes, you drive the alternator all the time, but it is fitted with a regulator that maintains the voltage in the car's electrical system at around 14volts with the engine running. Now, if the car is not using much power (dry, daylight) and the battery has been charged since the last start the alternator won't be doing much. However, on a cold, wet, night (so main beam, blower, heated screens etc) you need much more power - the regulator alters the output of the alternator to match the power requirements so you don't drain the battery. More power out = more power in required, so the engine has to work harder to keep up.
Think of it like driving the car - you drive along the level at a throttle opening and the car stays at the same speed. You then encounter a hill (like loading the alternator up) and the car begins to slow down. You apply more throttle (like the alterntor taking more power out of the engine), which puts more fuel into the engine - BUT the engine doesn't speed up, it is just working harder at the same speed.
Hmm, that's not a brilliant analogy, but the best I can think of at the moment!
Richard
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RichardW, thanks for the explanation and clearing that one up - another one of *my* theories goes up in smoke! :-)
Chad.R
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No problem - let's hope your alternator doesn't go up in smoke as well.....
Richard
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