Anyone supercharged the ND?

If so, the 1.5 or 2.0?

I’d be tempted to do so with my 1.5 at some point.

Sorry - but this invokes the comment “Why did you buy a 1.5L car when the 2L has more power, and has better economy?” Presumably the price difference made the choice? You are probably revving the heart out that engine, and getting nowhere fast enough, hence the need for speed. Price difference? Yes, but you are now thinking of spending more money on getting more power out of an engine not designed to provide it normally. Any means of powering up an engine involves more fuel usage, so long term, you will be laying out the same price difference between the 1.5 and 2L engines. Think about it, is all I have to say. Not aware anyone has done this - yet, but being the first needs thought on your part.

Not what you want to hear, but that’s my input anyway. (I did say Sorry to start with.)

In answer to your question, no, I don’t think it’s something that’s easily done with the ND. The BBR Turbo route would be a better option I’d have thought. They’ve put proper investment in getting it right, and do 1.5 or 2.0 options. Not cheap - but then neither would a half decent supercharged option be, particularly given the time and effort to make it reliable.

The ND gearbox struggles with the standard power so why stress it more by turbo or supercharging it? You will invalidate your warranty and have a £2k bill for a new gearbox if/when it goes bang.

Money wasn’t the deciding factor at all, I test drove both and didn’t like the old 2L engine. It was designed around the 1.5 and the 2L was made more for the American market. What are you on about more economical? The 1.5L engine is more than 2 years newer than the 2L.


And no, there’s no need for speed, I was just genuinely curious. 


If you look on there are loads of posts from people who have supercharged or turbocharged their cars, nearly all 2.0 but there are a few 1.5s


Edelbrock do a Supercharger for the ND, not seen anyone post about fitting other than Turbo to the 1.5 though.


There‘s much more of a difference between the 1.5 and 2.0 than displacement. The car was conceived and designed around the 1.5 with the 2.0 engine being much less developed from its starting platform than the 1.5. The 1.5 excels over the 2.0 on fast twisty A roads where the 2.0 is competetent, the reverse on a motorway (only if you must) where the 2.0 has more grunt for long hills. The 1.5 is lighter too, always an advantage.

The 2019 (US model year designation) 2.0 is getting some upgrades to bring more horsepower and a higher red line (currently the 1.5 revs higher and more freely), it will be very interesting to see what this does to the character of the car.

The term ‘economical’ is generally used as the cost of running a car, based on reports from Mk3 ownrs of 2L cars, there were various reports of more than 40 MPG. To - me, that’s economical. I’m disregarding comments made about the design of the 2L engine, which was described as “Half finished” in the sense that it was released prior to any improvements. I’ve not seen any reports yet from either Mk4 1.5L or 2L engined cars, but the 2L was reported as having more low down torque than previous engines, and it’s torque that moves mass, while bhp is reported as 160 (158?) bhp on the 2L engine. What is it on the 1.5L?

The following comment about 1.5L engined gearboxes struggling with power, appears to be a misnomer, according to reports, it’s the 2L engine  and the final diff gearing that is stressing the gearbox  in a few cases on road cars, and apparently, more so under race conditions. No-one is racing a 1.5L car.- That speaks volumes to me.

And - A 1.5L engine is revvier than a 2L doesn’t hold water, you don’t need to rev a 2L engine if there’s always more torque available at lower revs, it stands to reason that a lower revving car with more torque will move mass faster than a 1.5L version. No dyno figure have yet been published for either Mk3 or Mk4 cars, but it would be interesting to see a comparison. - No-one seems bothered these days, why is that? I found it extremely useful for everyday driving, as I know where the torque comes in, and the hp gradually levels with it. This allows me to drive while half watching the Tach, as it governs relative speed in any gear, and in that sense, more useful than a half baked speedometer - which reads 10% higher than it should.


The 2L isn’t as economical as the 1.5L, though. Why are you getting so riled up? I was just asking! 


I can‘t believe how economical the 1.5 is for the amount of fun it provides and as for the other part of your comment some people try to use theory to support a position without having any real experience of the subject at hand… if torque is your thing buy an oil burner.

There are loads of Dyno graphs for the ND on Miata .net 



Whose getting riled up,? -  I was just commenting too.

The actual reason I posted in the first place was to put your post out in the open, as few would comment on it otherwise. Then I get a load of counter arguments from others. I have respect for anyone seeking more power, but my initial reply seemed obvious - as to choice of engine. If an owner of an ND 1.5L would like to post actual mpg, then I will withdraw my comment about economy, not seen that yet on here - or elsewhere. Proof is in the pudding! Not interested in day dreams, reality counts.


I have a 1.5L and regularly smash it to 60 and still get over 50mpg.


Ian - I already have an oil burner thank you -it powers our central heating.

Have you ever seen a V8 rock? - I have, it’s called counter torque, a force equal to an opposite reaction. (owned two V8’s in my life) BUT - I’m talking about big V8’s, not 260  or 289 cubes. Some boosted V8’s (dragster specials) have so much counter torque they need extra bracing, to counter that reaction. Theory does not stand still, it’s often gained from practice. - Not always the other way round.

Old theory is being changed almost daily, as more and more people with inventive minds put them to the test. Both V8’s I once owned had redline at around 5-5.5K, look at F1 these days, far outweighs those limits. This passes on to road car development, so theory never stands still. - Again - proof is in the pudding. I don’t just use it, I learn from it.

Unleash that power, and the car will stand on it’s hind legs, so much that overpowered cars have a support wheel (or wheels at the back to counter that reaction. That reaction is torque, bhp comes in later. I may be ‘old school’ petrol head, but I know what torque is, thank you.


I only do short journeys in my ND 1.5l, (Max 131 ps) shopping etc. once a week, 6 miles in each direction on a mixture of “A”, “B” and “windys” and I tend to drive it as if it were a sports car - average 46 mpg.

Afterthought:  Many years ago I had a Pug 205 1.9l GTI (130 bhp) which I drove over a similar route in a similar fashion - average 29 mpg.

If you’re looking for empirical evidence of ND economy levels to build into some hypothesis Gerry then 49.7 mpg average over 18,000 miles is mine, 1.5 in case that wasn’t clear, the one that loves to be revved (129bhp @ 7000rpm / 150nm @ 4000rpm, 0 - 60 8.3s). 

Cant comment on real world economy figures for the 2.0 (158bhp @ 6000rpm / 200nm @ 4000rpm, 0 - 60 7.3s)

I’ve got a 2.0 RF, only done 1300 miles in it so far, the average is 41.7mpg I don’t exactly hang around in it either

Minor corrections, unless it has deviated from the Jan 17 brochure specs at any time maximum torque comes at 4800 in the 1.5 and 4600 in the 2.0.

On that basis, the “low down torque” isn’t going to be so different.  Of course the 1.5 feels as if it has no torque at all when I have just got out of my wife’s 1.2TSI or my 2.4 turbo diesel.  But that is to compare apples and monkey nuts.

We all used to drive naturally aspirated (N.A.) petrols and, well, they have to be driven even if you are happy to pootle which only requires about 50bhp anyway (and that was about all they had when I had a 1965 Morris Oxford, 122Nm @ 2100rpm, 61bhp@4500 rpm.  0-60 in 23.7s).  I can still hear my dad saying “keep the revs up!”.

With a turbo, you can engineer a flat torque curve that starts low.  With a N.A. engine you can’t, and it’s actually beneficial to have that peak at reasonably high rpm otherwise you limit power (which is proportional to torque x rpm).

I drove both the 1.5 and the 2.0 before buying, and chose the 1.5.  It’s a bit slower if you get your stopwatch out, but I don’t race and it’s plenty fast enough cf. any speed limit in the UK.  The delivery is superb. 

At the time I preferred the looks of the Fiat 124, but I didn’t want that turbo - which, without a doubt, will make it ‘easier’ to drive.  But then my other car is easier still (it’s automatic).

Each to his or her own choice of course.