On 8/21/2010 11:40 AM, Donwill wrote:
> On 21/08/2010 16:35, NetMax wrote:
>> On Aug 21, 1:59 am, > wrote:
>>> On 20/08/2010 20:27, John McGaw wrote:
>>>
>>>
>>>
>>>> On 8/20/2010 2:21 PM, Tim M. wrote:
>>>>> On Aug 20, 3:30 am, > wrote:
>>>>>> An NA or NB Miata gets a bit
>>>>>> light on the steering at or above 120 without full ground effect
>>>>>> skirts.
>>>>> I was not aware that the Miata was capable of speeds above 120mph. I
>>>>> actually have always thought that they top out just below 110mph or
>>>>> so. Have I been wrong all these years? (Not that I am interested in
>>>>> checking it out in my '97 M-edition; I save the triple-digit speeds
>>>>> for my Ducati on the racetrack.)
>>>> I'm pretty sure that even the NA was good for at least 120mph or close
>>>> to it. I never had mine above about 100 indicated and it felt fine.
>>>> The USA-spec NC is rev-limited to 220k (137mph) and it feels as if it
>>>> will do it too.
>>> The latest (UK)MX5 brochure quotes 132 mph for the Sport Tech (soft top)
>>> and 136mph for the retractable hard top version, not that I'm
>>> interested in speeds above 85 mph (French Auto-routes) with very
>>> occasional bursts to 90 perhaps to get clear of difficult, potentially
>>> dangerous bunching on motorways.
>>>
>>> Don- Hide quoted text -
>>>
>>> - Show quoted text -
>> Curious why the heavier PRHT would be rated faster? If the engines are
>> the same, then the UK soft top must be getting different gearing (ie:
>> 5MT instead of the 6MT).
>
>
> Both have 6 Gears& ratios are the same, maybe the hard top has slightly
> less air resistance. However, the acceleration figures are also
> interesting:- Soft top 0 to 62 in 7.6 secs , Hard top in 7.9secs. Power
> to weight ratio has more influence at lower speed perhaps.
> Don

I think that you have it correct on it being the better aerodynamics
causing the higher possible top speed.

If I remember correctly, the PRHT assembly is 89 pounds, and the soft
top with frame is a little over 45 pounds, equaling less than 50 pounds
of weight difference.

Obviously, every pound counts for handling and acceleration, but not
necessarily on top speed with such a small difference.

Pat