Roadsters?

[Nomme de Plum]

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

Merc SLs start at 1800kg net weight and are big old beasts. Slightly more powerful for base model though at 380bhp

231kw sounds a bit low but electric motors have great torque from the start.

If it's cheap enough it will sell.

[bennno]

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

I'd suggest that 310 electric bhp's feel more like 450-500 ice bhp's in most driving situations

Ive been driving many years but i had a Test drive in an ionic 5 and went back to the dealer to ask if they had the 2wd drive version with 100bhp less to try, they told me thats what I'd been out in. So i bought the 180bhp version instead, which still has silly quick acceleration.

[Nomme de Plum]

f1eng said:

I’m not sure about an EV roadster.
Generally I like the quietness and instant throttle response of an EV daily, but for a fun car something rorty with 3 pedals, and no driver aids other tha ABS is what really appeals to me.

ABS.

We never had ABS when I was a lad.

[Nomme de Plum]

bennno said:

I'd suggest that 310 electric bhp's feel more like 450-500 ice bhp's in most driving situations

Ive been driving many years but i had a Test drive in an ionic 5 and went back to the dealer to ask if they had the 2wd drive version with 100bhp less to try, they told me thats what I'd been out in. So i bought the 180bhp version instead, which still has silly quick acceleration.

My taxi driver has a Nissan Leaf. It's a saloon and i think a similar 180bhp or maybe a bit less.

The acceleration at legal speeds is pretty spectacular.

Edited by Nomme de Plum on Wednesday 12th April 16:56

[andburg]

bennno said:

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

I'd suggest that 310 electric bhp's feel more like 450-500 ice bhp's in most driving situations

Ive been driving many years but i had a Test drive in an ionic 5 and went back to the dealer to ask if they had the 2wd drive version with 100bhp less to try, they told me thats what I'd been out in. So i bought the 180bhp version instead, which still has silly quick acceleration.

Exactly my point, too big, too powerful!

150-200bhp and mx5/MG TF size was what I expected.

[starsky67]

andburg said:

bennno said:

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

I'd suggest that 310 electric bhp's feel more like 450-500 ice bhp's in most driving situations

Ive been driving many years but i had a Test drive in an ionic 5 and went back to the dealer to ask if they had the 2wd drive version with 100bhp less to try, they told me thats what I'd been out in. So i bought the 180bhp version instead, which still has silly quick acceleration.

Exactly my point, too big, too powerful!

150-200bhp and mx5/MG TF size was what I expected.

The trouble is there is a minimum weight that you need for a decent battery pack size, the power comes at relatively little cost so you’re not going to see an EV Elise so much as something with 1300kg at least. But takes something like an i3 spec drivetrain and it’s not a bad starting point

[andburg]

Absolutely get that big batteries mean weight but it’s not a repmobile, it doesn’t need 300 miles of range

50kwh battery and 220m range with 200bhp to the rear would have been nice, even with the weight being 1600kg which r whatever it should have had more than enough power.

Drop the roof and you slow down so you don’t mess up your hair

[Nomme de Plum]

starsky67 said:

andburg said:

bennno said:

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

I'd suggest that 310 electric bhp's feel more like 450-500 ice bhp's in most driving situations

Ive been driving many years but i had a Test drive in an ionic 5 and went back to the dealer to ask if they had the 2wd drive version with 100bhp less to try, they told me thats what I'd been out in. So i bought the 180bhp version instead, which still has silly quick acceleration.

Exactly my point, too big, too powerful!

150-200bhp and mx5/MG TF size was what I expected.

The trouble is there is a minimum weight that you need for a decent battery pack size, the power comes at relatively little cost so you’re not going to see an EV Elise so much as something with 1300kg at least. But takes something like an i3 spec drivetrain and it’s not a bad starting point

It's a shame that BMW didn't create a cabriolet version of the I3. Too little demand i suppose, but who'd have put money on a Cabriolet Range Rover.

Something like the MX5 hits a sweet spot. The people who just like a drop top and not bothered by anything else and those who like balanced handling.

[Nomme de Plum]

andburg said:

Absolutely get that big batteries mean weight but it’s not a repmobile, it doesn’t need 300 miles of range

50kwh battery and 220m range with 200bhp to the rear would have been nice, even with the weight being 1600kg which r whatever it should have had more than enough power.

Drop the roof and you slow down so you don’t mess up your hair

Hair?

So last year!

[TheDeuce]

andburg said:

Absolutely get that big batteries mean weight but it’s not a repmobile, it doesn’t need 300 miles of range

50kwh battery and 220m range with 200bhp to the rear would have been nice, even with the weight being 1600kg which r whatever it should have had more than enough power.

Drop the roof and you slow down so you don’t mess up your hair

I generally agree and have already said on this thread that a fun roadster EV is probably best with less batteries as most owners don't need great range - they literally just want a fun toy to bomb around in. Manufacturers should at least offer a lightweight, cheaper and shorter range variant. I suspect they probably will, it's kind of a no brainer.

But that said, the 'MX5 equivalent' EV, even with limited range, will still weight a little more and to offset that a slug of extra power and torque is sensible. The extra power/torque required won't make it undriveable or any heavier than if it had just 200hp. It'll simply counter the weight gain. Power is cheap to the point of being almost free when it comes to giving a car an extra 100hp in EV world

I appreciate that the joy of the MX5 is that it doesn't need great power to be great fun, but sometimes it would be nice to have the extra straight line poke. I appreciate also that extra power in the MX5 could spoil the sportier driving fun because, sooner or later on its skinny tyres the extra power would catch you out... But electrical power is so much more precise both in terms of driver control and electronic torque control that I don't think that it would be at all sketchy.

We just need Mazda to take the jump and make the car - I don't know what's holding them back to be honest. It doesn't even need to be a 'good EV' in terms of efficiency or range or charging speed etc, it just needs to take what is fun about the electric power train and apply it to a properly fun car. I really don't think prospective buyers care about much beyond how fun the car is.. so long as it gets along the same roads as fast or slightly faster (it would) and costs half as much to run then it's going to tick boxes. And as a bonus, it'll offer properly fun straight line acceleration and a more substantial kick out of a corner too. I'm not suggesting these new potential upsides are better than an ICE engine note and manual box, but don't properly the entire package could easily be as satisfying overall, just in different ways.

Having said all that about what an EV MX5 could deliver - if the MG gets it right then they'll take an early lead in EV roadsters and it might prove to be one Mazda can't counter, perhaps they've already left it too late to transition to EV for the MX5. They should have been first really.

[starsky67]

Nomme de Plum said:

It's a shame that BMW didn't create a cabriolet version of the I3. Too little demand i suppose, but who'd have put money on a Cabriolet Range Rover.

Something like the MX5 hits a sweet spot. The people who just like a drop top and not bothered by anything else and those who like balanced handling.

Yes, the closest to a true lightweight roadster in an EV so far was the original 20kWh (69Ah) i3 at 1195kg

That had an expensive carbon fibre core, so a roadster based on that approach would probably be around £30k I’d expect.

It’s hard to see a market for that while petrol alternatives still exist.

[otolith]

I wonder how much more inherently expensive a carbon tubbed roadster would be than a carbon safety celled closed car like the i3.

[starsky67]

That’s the car Gordon Murray should be making!

[TheDeuce]

otolith said:

I wonder how much more inherently expensive a carbon tubbed roadster would be than a carbon safety celled closed car like the i3.

Would probably need very high sills and subsequent some weird door/window designs to be strong enough and also real world affordable.

Creating a low enough sill for a traditional car door and also no roof removes so much from the structure that what remains has to be made extremely strong and rigid. The job would be made harder still if there wasn't a transmission tunnel to acts as a strengthening rib running the length of the car.

But, better lightweight car design including more mainstream use carbon fibre will hopefully progress as it's clearly a way to increase range whilst 'better batteries' remain elusive.

[starsky67]

TheDeuce said:

otolith said:

I wonder how much more inherently expensive a carbon tubbed roadster would be than a carbon safety celled closed car like the i3.

Would probably need very high sills and subsequent some weird door/window designs to be strong enough and also real world affordable.

Creating a low enough sill for a traditional car door and also no roof removes so much from the structure that what remains has to be made extremely strong and rigid. The job would be made harder still if there wasn't a transmission tunnel to acts as a strengthening rib running the length of the car.

But, better lightweight car design including more mainstream use carbon fibre will hopefully progress as it's clearly a way to increase range whilst 'better batteries' remain elusive.

Essentially an updated version of the Tesla roadster (whether with a carbon tub and extruded aluminium chassis) is what is needed. The trouble is that even Lotus can't make something that light anymore with a traditional powertrain(look at the Emira)., The chances therefore of any mainstream manufacturer making a lightweight EV roadster seem very slim, leaving it to small volume marques where the exotic construction needed and lack of economies of scale mean that it is virtually impossible to do it cheaply.

I suspect that EV roadsters will therefore be heavy and more GT like (eg the MG

Even the specialists like Ariel seem to want to go for more power to overcome the weight and then add downforce to improve cornering performance. No one seems to want to go for low weight/ low power in an EV, I suppose it's a hard sell when others can offer so much more performance on paper. Ariel's Hipercar is 1500kg for example.

An 110kg EV based on the original i3 powertrain would be marvellous but would be a sales catastrophe I expect. Not enough people care enough about weight more than power to make it feasible.

Even the proposed electric Alpine/ Lotus are tagged fro 1380kg, that's about as light as mainstream EV sportscars are going to be.

An Elise S2 is what, 710kg?

[TheDeuce]

starsky67 said:

TheDeuce said:

otolith said:

I wonder how much more inherently expensive a carbon tubbed roadster would be than a carbon safety celled closed car like the i3.

Would probably need very high sills and subsequent some weird door/window designs to be strong enough and also real world affordable.

Creating a low enough sill for a traditional car door and also no roof removes so much from the structure that what remains has to be made extremely strong and rigid. The job would be made harder still if there wasn't a transmission tunnel to acts as a strengthening rib running the length of the car.

But, better lightweight car design including more mainstream use carbon fibre will hopefully progress as it's clearly a way to increase range whilst 'better batteries' remain elusive.

Essentially an updated version of the Tesla roadster (whether with a carbon tub and extruded aluminium chassis) is what is needed. The trouble is that even Lotus can't make something that light anymore with a traditional powertrain(look at the Emira)., The chances therefore of any mainstream manufacturer making a lightweight EV roadster seem very slim, leaving it to small volume marques where the exotic construction needed and lack of economies of scale mean that it is virtually impossible to do it cheaply.

I suspect that EV roadsters will therefore be heavy and more GT like (eg the MG

Even the specialists like Ariel seem to want to go for more power to overcome the weight and then add downforce to improve cornering performance. No one seems to want to go for low weight/ low power in an EV, I suppose it's a hard sell when others can offer so much more performance on paper. Ariel's Hipercar is 1500kg for example.

An 110kg EV based on the original i3 powertrain would be marvellous but would be a sales catastrophe I expect. Not enough people care enough about weight more than power to make it feasible.

Even the proposed electric Alpine/ Lotus are tagged fro 1380kg, that's about as light as mainstream EV sportscars are going to be.

An Elise S2 is what, 710kg?

Yes they will be heavier, there's no way around that at least until far higher density battery tech is proven and mainstream - that will happen at some point, but no time soon.

As I said earlier, the cars can be 'light enough' for the sharper power response, higher power levels and vastly improved weight distribution to offset the weight penalty - at least for driving on the public roads where you can never push to the limit in anycase. On a track, the lightweight ICE car remains superior, especially in fun terms.

[TheDeuce]

starsky67 said:

Nomme de Plum said:

It's a shame that BMW didn't create a cabriolet version of the I3. Too little demand i suppose, but who'd have put money on a Cabriolet Range Rover.

Something like the MX5 hits a sweet spot. The people who just like a drop top and not bothered by anything else and those who like balanced handling.

Yes, the closest to a true lightweight roadster in an EV so far was the original 20kWh (69Ah) i3 at 1195kg

That had an expensive carbon fibre core, so a roadster based on that approach would probably be around £30k I’d expect.

It’s hard to see a market for that while petrol alternatives still exist.

I think £30k would be seen as a bargain by many for an EV roadster - but let's go with that figure for now and compare it to the ICE MX5, which I see is £28k in decent trim.

The proposition would be:

Does Sir want the latest MX5, here it is - lovely isn't it.

Or... Would Sir consider the new EV model? First the bad news, it no longer makes vroom vroom noises and there's no waggly stick to move around the place. On the upside, we have managed to drop the CoG from above the axle centres to beneath them, we have also achieved perfect weight distribution, increased throttle response by 200%, added 100hp, doubled the torque output and flattened the torque delivery curve, reduced servicing costs by 50%, running costs by as much 70% (hands customer a guide to off peak charging), reduced the 0-60 time by 2 seconds and the brakes will last twice as long. - Pauses for breath - RFL is reduced by 80%, the car will defrost itself on a frosty morning or cool the interior on a hot day, it will never need to be warmed up before you thrash it, full power is available the moment you set off and when you're stuck in traffic it's silent, smooth and relaxing to drive.

I think such a proposition would at least elicit genuine interest from most prospective buyers of a new MX5 - and a test drive in both cars might leave something of a difficult decision to make - because for everything 'pure' that is compromised in a roadster as they move to EV, there are other things that are improved.

Of course until we can see the final specs and drive whatever EV roadsters are on the way, it's basically impossible to know if they can do enough to compensate for what will be missed from the outgoing ICE models. But I suspect they can.

[kambites]

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

It would be a really odd decision to make it that big and heavy given that it's apparently based on the MG4's platform. I'd have guessed the entry level car would have similar specs to the MG4, so around 1600kg, 200bhp and about the size of a Boxster; with the top spec cars running two motors and around 400bhp. Hopefully the price wont be massively more than a comparable MG4 either, so around the £30-35k mark for the entry level model.

[starsky67]

kambites said:

andburg said:

I just cant get over the supposed figures

1.8t and roughly 2ft longer and 1ft wider than an ND MX5 with the base model and a base power of 231kw (310bhp)

at that size and power it feels like its going to be well wide of the mark

It would be a really odd decision to make it that big and heavy given that it's apparently based on the MG4's platform. I'd have guessed the entry level car would have similar specs to the MG4, so around 1600kg, 200bhp and about the size of a Boxster; with the top spec cars running two motors and around 400bhp. Hopefully the price wont be massively more than a comparable MG4 either, so around the £30-35k mark for the entry level model.

So even at 1600kg, the weight of a BMW 650i (1615kg) with less power (200 vs 367hp) and fewer seats. You can see the problem.

For the next 15-20 years, your best bet if you want a lightweight roadster is to buy a lightweight petrol roadster and keep it in good condition until battery tech improves.

[kambites]

starsky67 said:

So even at 1600kg, the weight of a BMW 650i (1615kg) with less power (200 vs 367hp) and fewer seats. You can see the problem.

An old 650i maybe. There's no way a current 6-series is going to weigh under 1700kg.

Modern cars are heavy; EVs are, generally speaking, even heavier. That's just life. To compare it to modern sports cars 1600kg would put it around 100-150kg heavier than a Lotus Emira; about the same weight as a BMW Z4; 250kg heavier than a Boxster; 100kg heavier than an Audi TT... so while it would certainly be no lightweight, it wouldn't exactly be an order of magnitude heavier than ICE competition aside from the MX5 which is very much an outlier.

If you want a lightweight roadster, by one from the 60s.


I certainly wont be trading my Elise for one, but then I wouldn't trade my Elise for anything else currently on the market either, be it ICE or EV. If they match the specs of the MG4 it will be perfectly adequate for most sports car buyers, and if can even get close to the price of the MG4 I suspect it will sell in huge numbers. If it ends up being two meters wide, weighing nearly two tonnes and costing £50k, they've completely missed the mark IMO. We will see...

Edited by kambites on Thursday 13th April 17:29