Recent content by Fogey

Just a word of warning - the accuracy of tyre pressure gauges isn't something that you can necessarily rely on. Here's one which at least has something of an accuracy spec: https://www.pclairtechnology.com/tyre-pressure-gauge-in-line-head-psi-bar Watch out for cheap knock-offs though. Caveat...

Thanks for that. Yeah, it's a pity, because the MG4 is one of the best looking cars on the road, in my opinion - and it drives to match.

That, more than anything else, has finally put me off buying an MG4, I'm afraid.

Very nice - would be good to use this for the MG4 if we could get some info on things like rolling resistance, drivetrain efficiency etc. Some of these could be estimated if someone could perform some rather tedious tests, I suppose. At motorway speeds, aero drag probably dominates by some...

Last para of post #15 was originally a separate post. Which led to me thinking it was a third FM - hence my later reference to "at least one...".

I see the Mods have been at work - Edits now seem to be flagged (though not retrospectively), also a couple of posts seem to have been merged. Actually, they'd do well to delete all posts after #14. Do a Patrick Duffy, as it were... Hmm - but not that last post, which was edited, but not...

The point is that you contradicted my post by saying that the figure should have been 5.98 kWh. Which was INCORRECT - hence my response. You then admitted your mistake, so I repeated the the figure of 1.5kWh as being the correct one, and not 5.98kWh. But it's apparent that you edited your...

OK, as at least one FM is now feeling confused, I'll repeat, the correct figure is: ~ 1.5kWh per 1000 feet.

No it's not - I think you've mixed up hours and seconds. Edit: in response to @wattmatters' comment.

Yes, as I said, the energy per 100 miles is a more useful figure (as it has a more direct relationship to range - which very much is a limitation). By the way, the energy figure for lifting an MG4 1000 feet is about 1.5 kWh. (Not a lot of people know that!)

What I was saying was that weight isn't a factor which affects drag - and the figures are for aerodynamic drag only. Energy required to overcome rolling resistance (which is pretty much constant for a given weight over a given distance/route) and in changing speed are of course extra.

You both may find this interesting: https://www.mgevs.com/threads/mg4-drag-various-conditions.8275/#post-133694

I don't think you need to worry about seals in the case of A/C in EVs (or hybrids), as they are self-contained with internal electrically-powered compressors (like a domestic fridge) - unlike ICE cars, where compressors are driven mechanically via an external pulley driven by the engine.

EVs' motors are torque-limited (i.e. constant-torque) at low-speeds, and power-limited (constant-power) at high speeds. There is also the motor temperature factor - the quoted maximum power is, I believe, a peak power figure. As to how long you can maintain that - it doesn't seem to be well...

Don't forget that, regardless of battery considerations, the increase in air density with colder temperatures will cause an increase in drag - expect at least 15% more drag at motorway speeds if it's -30C (compared with an air temperature of 15C). Since drag losses dominate at motorway speeds...