Question about weight

[Tim_Headford]

Does anybody know how much my car weighs?  I know the stock figures (although people seem to differ even on those) but I’m sure mine but be lighter due to the spec.

It’s a 1996 1.8 UK spec. but has no power steering, no airbags, no heated seats, no ABS, no electric windows, no nothing.  Surely those things must all weigh something, but is the official weight just the car BEFORE those things are taken into account?

Thanks in advance.

[Drumtochty]

Stop messing about comparing weights from different sources and then posting about what the weight is.

There will be a local weighbridge somewhere near you.

They will be delighted to tell you the exact weight of your car if you drive it on to the weighbridge.

[Paul_G]

The lightest of all will be the Mk 2.5’s.

 

The chassis rails on these weigh almost nothing at all.

 

 

 

[Tim_Headford]

Haha no doubt. I just wondered whether the lack of equipment got mine back under the magic tonne like the 1.6.

[rhino666]

It must be on the lighter side as I have a similar aged MK1 with the detuned 88bhp 1.6 engine and there really isn’t that much performance difference when compared to Our Eunos with a good 115bhp engine. 

Aircon, power steering, etc must add 20 - 30kg.   

[BurtonM]

The local steel stockholder weighed my motor home on his weigh bridge, front axle, back axle then both. £5.00 with a print out.

[Coops_Mk2]

As above, best bet is to find a local public weighbridge and just weigh the thing. 

For vague comparison my mk1 clio which weighs about 1000kg stock I’ve completely gutted, right down to no dashboard or blowers etc but with a full cage adding weight back in and that’s 850kg on the bridge now

[ast]

@rhino666

It must be on the lighter side as I have a similar aged MK1 with the detuned 88bhp 1.6 engine and there really isn’t that much performance difference when compared to Our Eunos with a good 115bhp engine. 

Aircon, power steering, etc must add 20 - 30kg.   

 

On paper, the detuned model was over a second down 0-60 on the earlier car, and that was after the various weight saving Mazda carried out on this model (and maybe timing tweaks to try and narrow the gap)

 

While there is debate about the savings removing chassis bracing, PAS pump, ABS (most MX5s never had this), to counter balance that, you also need to include consideration of the additional 21lbs from having the 14" steel wheels fitted (what most base models received), which is 21lbs (~10kg) increase in unsprung weight (arguably, a greater impact than 21lbs lost in the engine bay), and the impact having the slower (ratio) manual rack fitted (the manual rack is not the power rack depowered (2.8 turns lock to lock on PAS, 3.3 turns on manual racks).

 

The usual effect of aircon on performance, in older cars, is a drag on performance. I had a 1992 Honda CRX HF; billed as the lightweight special (no back seat, parcel shelf, single mirror, slim seats), in reality, it was the wheezy 70hp model designed to meet CAFE, and pull Honda’s average MPG up. The aircon in that car was dumb; switch it on, and it felt like suddenly a sack of spuds was thrown in the back. In the MX5, its a cleverer system; under wide open throttle, the aircon clutch will disengage. In otherwords, day to day driving, the only difference you will notice is slightly worse MPG. Traffic lights drag; no difference, and the Eunos wins out on the right hander, because of its vlsd.

 

 

Aircon: +20kgs

Power steering pump/reservoir: +4kg

ABS controller: +3kg (about)

1.8 Subframe braces: +2kg (about)

Cockpit brace: +1kg (about)

Power windows: +2kg

14" steel wheels: +10kg

 

Eunos kerb weights:

https://www.mx5oc.co.uk/forum/yaf_postst113242_Eunos--Weight-Difference-between-1-6-and-1-8-cars.aspx

 

The 1989 Eunos Roadster is close to the stripper poverty spec 1997 1.6.

 

On paper, the Roadster (no braces, with PAS, PW, alloy wheels): 940kg (115hp)

On paper, the UK 1997 1.6i was 922kg (88hp)

 

Still not enough to overcome the power-weight ratio deficit.

 

The 1.8i would be about 954kg, versus 980kg of the run out S-Package. But that run-out S-Package had a 4.3 Torsen not the 4.1 open diff, so quicker off the line, and through the corners.

[Tim_Headford]

Thanks, good info.

So I assume that listed curb weight of 954kg is the base car without the extras. So since mine has only the 1.8’s extra bracing, I should be under that tonne mark. Happy days!

Cheers.

[ast]

No, 954kg is a educated guess, based on how kerb weights are measured for the Japanese market, which is different from the European and US markets. And you are still left with a steering rack that is hated by the designers of the MX5, the heavy flywheel, and heavy steel wheels.

Bob Hall (Father of the Miata) hated the manual rack. And has ranted about it for the last 30 years, if anyone would care to ask him. Having had a M2-1002, with that infamous steering setup, I can agree with his sentiments. Some quotes from him:

My biggest complaint is that the (manual) rack is so damn slow. Just shy of a complete turn lock-to-lock is slow in my book, but then I wasn’t raised in or around Detroit Iron. I was pretty appalled when I learned that there with cars requiring more than 3.5 turns lock-to-lock. Being dropped into a Plymouth Fury III is a bad way to start Driver Training when you’ve been spending all your clandestine wheel time in things like an Austin-Healey 100S, MGA Twin Cam and an XK-SS…Of course if Hirai-san and Kijima-san got their way, people everywhere would be waxing lyrically about the Miata steering, as there would be no reference point to base the non-assisted argument on. Not a mistake which will be made again when the NC rolls around.

At center, the non-assisted rack is woollier, artifacts of the underdevelopment it received from coming into the program so late as well as an effort to reduce kickback. The original go-around was a thumb-breaker over some common road surface disruptions.

Unlike subjective feel, the benefits of the quicker rack cannot be denied, at least by anyone who understands that a quick steering ratio is part of the fabric of any sports car. Those into philosophy to the exclusion of fact are unlikely to be swayed, however.

Mazda’s chief test driver when the Miata was underdevelopment along with one of the factory race drivers (Terada-san, I believe) both mentioned that the non-assisted steering could be appreciated by those who were accustomed to wrestling with a car, and that the power steering would be more rewarding to a driver understanding and using delicacy while behind the wheel.

Of course if the Program Manager and the chassis development team had gotten their way, this argument would never have existed in the first place.

As steering systems designed and partially tested and signed-off in a 60 day period, the Miata’s non-assisted tiller is one of the best. Mind you I can’t think of any other car to have a non-assisted steering system tossed into the development program as late as the Miata’s was, so to be fair it is the best in a small field.

I was always fascinated that all the guys in chassis development - including the test drivers - who purchased Miatas (well, Eunos and mazda Roadsters actually) bought cars with power steering.

Because non-assisted steering was not part of the original package, the development team - and especially the Program Manager - were not anxious to add it. Only when the US importer said that cars with the non-assisted steering would make up at least 20 percent of volume (though in fact demand for some has never been more than 12 percent of the total US volume) was a non-assisted tiller forced upon the development team.

In addition to taking staff off the power system fine tuning, this diverted people from engine layout sign-off. As a result, instead of having the normal 200 days to develop the system, only 60 days (58, actually) were available. And to me it shows. While what appears to be feel (but to a large degree is column-induced friction) seems better than the power system, it is woolly at center and loads up too quickly. As non-assisted steering goes, [b]it is trashed - utterly - by the system Nissan put in the March, a 1.0 to 1.3 litre car not sold in North America[b]. Worse yet, the Nissan March is a front-driver. And my criticisms of the non-assisted steering in the Miata go beyond the slow ratio, though that part’s an unforgivable sin in a sports car.

Still some people swear by the non-assisted rack. It’s a matter of taste to a huge degree and I am certain there is some subconscious rationalisation in there as well as philosophical weighting.

Philosophy is important in a car like the Miata, but it’s all-too-easy to let it get in the way of improvement. I don’t see many people complaining about the Miata using disc brakes and having electric starting, but I suppose power steering must be some sort of newfangled abomination to some people.

One of the guys in Chassis Development who still has his 1990, tweaked the power steering to what they had intended the production car’s to be (and probably would have if there hadn’t been a dispersion of manpower to develop the non-assisted rack). It’s about the second or perhaps third best power steering I’ve ever driven (after BMW M3 and about line ball with Maserati 3200GT), and impressive by anyone’s standard. Perhaps in the vein of what might have been if the original development schedule had not been derailed.

The non-assisted tiller is utter ■■■■. I wouldn’t own a car with the non-assisted rack on a bet, though I would unhesitatingly and wholeheartedly recommend one to my worst enemy or the President of the Honda DelSol Owners Club.

I like non-assisted steering. Equally, I like power-assisted steering.

What I don’t like is bad steering.

In this particular context the concept of ‘bad’ applies equally to a vague, overassisted power tiller as it does to a non-assisted one which exhibits excessive column/rack friction (which people somehow equate to ‘feel’) and/or loads up at the sight of a curve. And with my reference points, the non-assisted steering of the Miata (NA or NB) qualifies as bad.

There’s a lot to the old adage of “the best you’ve driven is the best you know”, which is why I suspect the non-assisted system has the proponents it does.

Unfortunately I’ve driven too many cars with non-assisted steering which place the Miata’s in a negative light. Mind you this is neither especially good nor hideous if taken as an absolute. However, in the context of a reasonably lightweight sports car absolutes are exceedingly difficult to apply and/or rationalize; context is what denotes the difference between that which may be merely acceptible and that which is exceptional.

The Miata’s non-assisted steering is - based on my reference points - nowhere close to the level of competence displayed by rest of the Miata’s chassis. Which means it’s not as good as it should be.

When price-engineered econoboxes like the second-generation Nissan Micra/March have better on-center feel, still with a quick ratio and are utterly devoid of load-up as lock is applied, the inadequacies of the Miata’s non-assisted steering become readily apparent. I won’t even raise the subject of things like the delightful non-assisted steering gear of Series I through SE Lotus Elans, as such comparisons cause the position of the Miata to become even more odious.

Given the work which the development staff put into the Miata, it deserved better than the underdone non-assisted steering forced upon it by unwarranted concerns from an offshore sales department. And the proposed assisted set-up was indeed a delight on the mules I drove with it. As stated in an alternate thread, it was perhaps the second-best power-assisted steering set-up I’d ever driven. Not bad when the only things better – or at least as good – cost a minimum of six to ten times what a Miata does.

As Gordon correctly pointed out, the tweaks to the power steering used on 1994 and later NAs (as well as NBs) embodied some of the work which had been done for the original gear and is better in terms of the subjective aspects of the assisted steering where the hardware in 1.6 litre NAs falls short.

Well, at least to me. But I like anchovies on pizza, all the Thin Man movies, blonde Asian girls who wear pink thigh-high boots with matching microdresses (so I married the second one I could find), every record/CD written or recorded by Yumi Arai/Matsutoya, and Watanabe Yoshimasa’s manga, so I will readily - and happily - accept that my tastes are not universal. Nor do I think they should be.

I’m still acutely peeved by the fact that if the development of the car had gone according to plan, there would be no non-assisted steering, period. Instead, the power system would have gotten the development and tuning it deserved (before the money stopped coming in as Mazda hit the wall financially in the late 1980s) and nobody would be any the wiser. Other than expressing delight at how good the Miata’s (power) steering was. The only griping would be coming from the mob who place philosophy before output. And they could always disconnect the pump.

Allegedly, the 96-97 PAS is close to what Mazda really wanted.