RE: Electrogenic Mazda MX-5 (NA) | PH Review
RE: Electrogenic Mazda MX-5 (NA) | PH Review
Wednesday 12th February 2025

Electrogenic Mazda MX-5 (NA) | PH Review

We've seen almost every engine swap possible into Mazda's iconic roadster - how about electric?


Modifying has been part of the Mazda MX-5 story almost since the very beginning: it was only 1991, remember, that the 787B famously won at La Sarthe, and the BBR Turbo Le Mans was created in celebration. Since then there have been supercharged MX-5s, rotary MX-5s, V6s, V8s - you name it, the MX-5 has probably been powered by it.  

And now there’s a battery-powered one. The MX-5 here is the work of Electrogenic, the same folk who recently converted a DeLorean to EV power with deeply impressive results. Its MX-5 overhaul will become a commercially available kit in time; for now, it’s the result of a bespoke commission, a customer that wanted their MX-5 to fit in with the rest of the EVs on the driveway. It will primarily be used as a London commuter, complete with speed limiter for those pesky 20s, and even the most ardent combustion head can see why electric power would appeal if staying inside North and South Circulars. (The swap has been registered with the DVLA, so is now ULEZ exempt.)

Because this car had sentimental value for the family, it hasn’t been restored to the point of perfection, so the wiper arms remain a bit scabby, the paint less than perfect, and the interior still a feast of old plastic. This isn’t one of those flawless EV restomods; it’s a powertrain swap to make an old car faster, more exciting and better suited to what the customer wants to use the car for. 

Two-thirds of the 42kWh battery sits snugly beneath the pop lights, with the other third occupying the space that did have the fuel tank in. That required a bit of toing and froing, because battery packs aren’t the shape of fuel tanks, though the only real giveaway is a ‘diffuser’ underneath that shields it. There’s still a boot (and still some space with a charge cable in), and no incongruous modifications; there are small drive mode dials behind the gearlever, and for the speed limiter. The rev counter is now a neat power dial, resting at what was 4,000rpm then nudging right when on the gas and back towards lower revs when recuperating, and the fuel gauge now works for battery reserve. It’s all extremely neat, and very satisfying, the kind of attention to detail Electrogenic is rapidly accruing a reputation for. Time invested in the details, including its proprietary Vehicle Control Unit (VCU) that means battery power can work with the OEM dials and displays, really pays dividends.

Even from the passenger seat, the MX-5 is an intriguing experience on the road. It’s far from silent, for starters, with all manner of whirrs and buzzes and fizzes coursing through the car. Electrogenic has a custom torque tube to get the motor’s power to the wheels, and its reverberations can be felt as well. Even with battery power, this still feels like a classic experience, a good dose of its original character preserved. To have an MX-5 show off regenerative braking definitely takes some getting used to, as does one that responds this instantly; while throttle response would always have been a strong suit with the original twin cam, torque was not, and to have that immediacy combined with 228lb ft certainly makes for more exciting progress. 

Despite some additional weight, the Electrogenic car rides fluently enough, and the chassis actually feels a little sturdier than previous NA MX-5s even without any extra bracing. Perhaps the location and the mounting of the batteries is advantageous, or concentrating on the powertrain deflected attention. 

Our turn to drive comes at the Bicester Motion track, in properly grotty conditions that mean the wipers are never off. The MX-5 couldn’t be easier to get going, the gearlever nudged back from neutral for drive and off you go. While the Eco drive mode is fine (because it doesn’t drastically reduce power) the Normal setting works best for the half a dozen turns because the regen is then strong enough to hardly trouble the left pedal. Lift, pitch it in, feel the roll, adjust as necessary, pick up the throttle knowing you’ll get exactly what’s asked for and drive out of the bend. 

Or there’s scope to be sillier, by going in slower or bundling in with momentum and using that instant throttle to corner a little more MX5-ishly. And it’s brilliant because there’s no need to worry about revs or lag or throttle response. So it becomes easy (and hugely rewarding) to meter out exactly the power required for small skids in the rain or significantly more slithering about. And regardless of powertrain, there’s not much that feels better on four wheels than a tiny tonne of MX-5 going sideways. 

Sport mode might as well be a drift button, making the throttle as sensitive to provocation as your overly online auntie. Which is hilarious - the merest hint of throttle spins the rear tyres. But it says much of the inherent balance and Electrogenic’s clever calibration that the setting never feels overwhelming or daft - you’ve just got to be prepared to catch it. Most encouragingly, especially if we’re getting into the emotional side of this discussion and what electrification can bring, the three modes give the MX-5 very different characters. It’ll coast, almost glide along, it’ll very intelligently regen, or it’ll behave like a grown-up R/C car. For a car that’s famously never boasted much configurability at all, the little Mazda works brilliantly in all three. It’s an absolute hoot, more of an MX-5 more of the time - and we never did more than 70mph.

This has all been tailored to the customer’s liking, too, and would be for future builds. More or less regen could be introduced, more or less immediacy, probably some extra power if so desired. Indeed the Electrogenic car gave such a good show that it’s easy to imagine, sacrilegious though it might sound, a track car build, with the performance, fun factor and regen ability. The brake pedal feel is good when it’s needed as well. 

Certainly there was never a point when having a manual gearbox and less power felt like it’d be significantly more entertaining. And if we accept that MX-5s should be about fun above all else, the Electrogenic swap is a resounding success. The car is not stymied or sullied by batteries, it’s actually brought to life a little more by how it tests the chassis and flings the Mazda along. Which, yes, forced induction and increased capacity have been doing for decades now as well - likely for less money, too, with Electrogenic kit prices still to be confirmed. But crucially an EV swap feels like no lesser substitute, with so much of the same joy that’s come to characterise modified Miatas over the years. And which continues to do so. The client getting this one will surely be very pleased indeed - let’s hope more follow. 


SPECIFICATION | ELECTROGENIC MAZDA MX-5 (NA)

Engine: 42kWh lithium-ion battery pack, single electric motor
Transmission: Single speed fixed ratio, rear-wheel drive
Power (hp): 160
Torque (lb ft): 228
0-62mph: c. 6 seconds
Top speed: 115mph
Weight: c.1,100kg
MPG: N/A efficiency, 50kW maximum charge
Range: c. 150 miles
Price: TBC

Author
Discussion

MOOSECORTINA

Original Poster:

253 posts

108 months

Wednesday 12th February 2025
quotequote all
Range - Ha ha ha ha.

thepritch

1,564 posts

194 months

Wednesday 12th February 2025
quotequote all
MOOSECORTINA said:
Range - Ha ha ha ha.
Can’t recall the last time I did more than 150miles in one day in my NA MX5. In fact I did less than that last year!

Note to self : must drive my mx5 more!

The biggest loss to this MX5 will be no gearchange. That short stubby flick change was all part of the mx5’s character.

Zero Fuchs

2,749 posts

47 months

Wednesday 12th February 2025
quotequote all
Yeah, I did over 100k in my first MR2, mostly commuting 70 miles/day. Cost me a fortune in petrol. This would've been perfect in many ways.

Manual in the MR2 is great too, as is the 1.8 vvti. But as a commuter the drive to work was great but the home run less so, due to the traffic. One pedal driving would've been perfect.

I suspect the 42kWh battery will push the mass up but if 0-60 takes 6 seconds it likely a good compromise. My i3s is 1300kg and whilst my MR2 is more nimble, could accept a few hundred kgs tradeoff.

bigyoungdave

329 posts

56 months

Wednesday 12th February 2025
quotequote all
Each to their own, but this is not for me. I've owned an NB for 14 years and that stubby little gear lever and snicky change is what draws me back to it, even on a dark wet night like last night.

FarmerJim

829 posts

188 months

Wednesday 12th February 2025
quotequote all
What a pointless waste of resources.

Evanivitch

26,344 posts

151 months

Wednesday 12th February 2025
quotequote all
Ooh I do like that. Horrendously expensive I'm sure for the chess weekend car but nonetheless they've done a decent job of it.

wistec1

794 posts

70 months

Wednesday 12th February 2025
quotequote all
If there was ever there was a great drivers car that didn't need EV this was it.

cerb4.5lee

44,487 posts

209 months

Wednesday 12th February 2025
quotequote all
So you wake up on a nice sunny Sunday morning, and you just want to go for a drive for the sake of it. You've got one of these, and the manual ICE version parked next to it in your garage...so which one are you taking?

Predictably I'm taking the manual ICE version for the noise/engine/exhaust/gearbox...but what would you do?

86wasagoodyear

965 posts

125 months

Wednesday 12th February 2025
quotequote all
Article said: "the chassis actually feels a little sturdier than previous NA MX-5s even without any extra bracing"
Photo directly below that quote - a mahoosive strut brace. Hmmm.
Maybe this will work for the owner as a within-London commuter / open-top dustbin, especially with such limited range. But out of town - where an MX-5 truly excels - will be out of reach. Personally I'd have stuck to a tin-top electric urban commuter, and also saved the original mk1 car.

Zero Fuchs

2,749 posts

47 months

Wednesday 12th February 2025
quotequote all
cerb4.5lee said:
So you wake up on a nice sunny Sunday morning, and you just want to go for a drive for the sake of it. You've got one of these, and the manual ICE version parked next to it in your garage...so which one are you taking?

Predictably I'm taking the manual ICE version for the noise/engine/exhaust/gearbox...but what would you do?
I'd take my manual MR2 with sports exhaust every time.

But what's your ratio of Sunday drives vs every day commuting and other stuff? Sadly mine is like 100/1 in favour of everyday stuff nowadays. I still have no idea why I've so many cars when most of my driving requires having a 'drivers' car less and less.

These little roadsters are brilliant in so many ways. But even these can get tedious if you're stop/start in rush hour traffic every day. Fine if like us you have more cars than sense but back when I had no money, I'd have loved something like this 99% of the time. I'd have probably yearned for the engine/gearbox on the 1 day I got an hour to myself but it would've been a fair trade.

SDK

3,452 posts

282 months

Wednesday 12th February 2025
quotequote all
MOOSECORTINA said:
Range - Ha ha ha ha.
If it had more range, then you would be complaining about the weight /shrug

Thankfully - they chose the right one smile

J4CKO

46,821 posts

229 months

Wednesday 12th February 2025
quotequote all
FarmerJim said:
What a pointless waste of resources.
https://youtu.be/ian6NyXpszw?t=77

DaveyBoyWonder

3,867 posts

203 months

Wednesday 12th February 2025
quotequote all
I can see the range argument but a blat over the moors to Whitby gives the perfect excuse for fish & chips whilst its topping up the batteries so no big deal.

Its the cost that I could see being the killer. Half decent NAs are now what, £4k upwards and I'm imagining the leccy kit is going to be £10k+ at least? Is it worth it vs keeping that little zippy 1.6/1.8? I'm not so sure.

It is a cool little thing though and I don't say that about many EVs. I can get my head around the EV thing no problem - its just that the styling of modern cars leaves me feeling cold - mainstream EVs all look exactly the same.

Auchtermuchty

40 posts

19 months

Wednesday 12th February 2025
quotequote all
Mmmm, just like a delicious steak and ale pie, but paying extra to have the steak part removed.

WPA

14,654 posts

143 months

Wednesday 12th February 2025
quotequote all
wistec1 said:
If there was ever there was a great drivers car that didn't need EV this was it.
+1

Taz73

484 posts

41 months

Wednesday 12th February 2025
quotequote all
I like the idea and execution with this, costs are going to be prohibitive, obviously, Autocar also has a review and is speculating around £30k, whether that includes restoration work as well wasn't said, but most na's will be rusty and in need of some fettling, I know my eunos is.
I guess if it works for you, it works for you, for that money, if I had it, I would be tempted but would go down the route of a rocketeer build which I think with resto work would be similar costs. I don't think the mx5 engine is all that special to want to keep it, it's no flat six etc, the gear change is though, so as others have said, that's what I'd miss the most, but for this owners use case, the rocketeer build wouldn't suit within London so this EV conversion makes a lot of sense, that it's done so brilliantly lends itself to other use cases as well, so I can imagine it doing well.
I don't think the range is a problem for most na users, maybe when they were new and only cars, nowadays they're probably 2nd cars run as classics. Mine doesn't go far.

MrGeoff

771 posts

201 months

Wednesday 12th February 2025
quotequote all
I don't like or dislike this really but I have to wonder what most people who own these cars use them for. I'm going to say that if you own an MX5 it spends most of it's time in the garage/drive and you take it out when the weather is nice and you can enjoy the car. So with an engine laying it up for a period of time will be fine as long as you take the necessary precautions. With this one being a BEV what will the lifespan of the battery be and will the trade off be worth it is you do say 15k miles over 10 years?

cerb4.5lee

44,487 posts

209 months

Wednesday 12th February 2025
quotequote all
Zero Fuchs said:
cerb4.5lee said:
So you wake up on a nice sunny Sunday morning, and you just want to go for a drive for the sake of it. You've got one of these, and the manual ICE version parked next to it in your garage...so which one are you taking?

Predictably I'm taking the manual ICE version for the noise/engine/exhaust/gearbox...but what would you do?
I'd take my manual MR2 with sports exhaust every time.

But what's your ratio of Sunday drives vs every day commuting and other stuff? Sadly mine is like 100/1 in favour of everyday stuff nowadays. I still have no idea why I've so many cars when most of my driving requires having a 'drivers' car less and less.

These little roadsters are brilliant in so many ways. But even these can get tedious if you're stop/start in rush hour traffic every day. Fine if like us you have more cars than sense but back when I had no money, I'd have loved something like this 99% of the time. I'd have probably yearned for the engine/gearbox on the 1 day I got an hour to myself but it would've been a fair trade.
I don't use my 2 seater Roadsters enough either to be completely honest. frown

I have this lovely ideal in my head, and that is why I keep them, but life doesn't always work out like that though as you say. I'm grateful that my daily is at least entertaining when I want it to be in fairness(F82 M4). Plus my daily is also faster than my weekend cars too, so I got that wrong really perhaps as well? But at least I do get the opportunity to use that performance sometimes though, because I'm in it everyday.

jay-kay-em

344 posts

233 months

Wednesday 12th February 2025
quotequote all
Even I begrudgingly understand the concept that millions of people can't burn dinosaur juice just to get to work and back Monday to Friday. That has to change.

What I don't understand - and never will - is why this has to impact recreational vehicles and even worse - classics.


RazerSauber

2,897 posts

89 months

Wednesday 12th February 2025
quotequote all
86wasagoodyear said:
Article said: "the chassis actually feels a little sturdier than previous NA MX-5s even without any extra bracing"
Photo directly below that quote - a mahoosive strut brace. Hmmm.
Maybe this will work for the owner as a within-London commuter / open-top dustbin, especially with such limited range. But out of town - where an MX-5 truly excels - will be out of reach. Personally I'd have stuck to a tin-top electric urban commuter, and also saved the original mk1 car.
That strut brace is factory fitted to Eunos models I think. It's definitely OEM.

I like the idea. If you just want the looks and an EV then away you go. Perhaps people who have an auto one that fancy keeping it but changing to EV? It's a niche thing but seems to have been well executed and I like the idea.