Mr Morlock wrote:Insofar as radiators are concerned the best is OEM ( is SE the same as std ?) -better than the aftermarket junk and sometimes keenly priced as well . Also don't put in junk water pumps.
The SE Radiator from memory is slightly different to the standard NB, using a thicker core.
I believe the Automatic NBs also used a thicker core than the more common manuals, but i'm not sure if the SE and Auto one are the same.
With regard to the aftermarket radiators, the ones mentioned, Koyo/Mishimoto/Supermiata are all commonly used quality alternatives. Albeit somewhat costly (although probably comparable to a genuine Mazda one)
Water pumps are easy since even quality ones from GMB (a common OEM manufacturer) are relatively cheap, so there's very little reason to go for a no-name one.
I would strongly suggest spending extra on the timing belt, either Mazda or Gates brand.
When my car has it's belt replaced by a workshop down here at 100,000km they used some other brand.
after about 70,000km the teeth all stripped off it, costing me a tow home.
When I removed it to replace (and also confirm why it broke) it was some brand called "racer" which had written on the belt "replace after 80,000km", so even the manufacturer wasnt confident it would last the normal life.....
While a dead belt wont cost you an engine in an MX5, thankfully, it is a massive inconvenience.