don't know the answer to the thermostat part, but I recently ordered a radiator for a 92 and what I got was the superceded part number shown in the catalog as being for a 1994
and it came with a new cap
I order a set of thermostats and radiator caps for my Miatas from Mazda and got p/n BP6F-15-171A for the thermostats.
Does mazda use a different thermostat for the NA vs. the NB? The ones today I got look different that the ones I once got back in my NA days.
don't know the answer to the thermostat part, but I recently ordered a radiator for a 92 and what I got was the superceded part number shown in the catalog as being for a 1994
and it came with a new cap
2009 MX-5 STR and track toy
2003 Z06 -- Not a Miata, but 3200# and 400 RWHP is fun
OTM -- 2012 Sierra, 2016 Impala (Appliances)
So I found one of my old Thermostats from my old '92!
There is a difference!
NA p/n F201-15-171A
NB p/n BP6F-15-171A
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It seems the NB would have a higher flow rate. I wonder if they are interchangeable? The NA has a little check valve or something though. Actually I recall the 1.6 may have a different thermostat than the 1.8.
if you car is naturally aspirated, it doesn't matter.
FYI, the factory Evo t-stat apparently flows more water than anything else people can find.
TXMC: Drinkin, shootin, racin!
Iain
"We don't stop playing because we grow old, we grow old because we stop playing." - George Bernard Shaw
Most thermostats allow some water passage when closed to prevent cavitation in the pump and allow the heater to warm up sooner. I bet the small valve on the old one does the same job the two little half moon cutouts do on the new one. My guess anyway.
Stripe Das Sape
We are leading the world to democracy by example.
If "most thermostats allow some water passage", that would slow down engine warm-up. Every manufacturer wants quick warm-up. The water pump does not cavitate when the thermostat is closed, in fact the water bypass is fed from upstream of the closed thermostat (that's why we call it a bypass). The tiny "burp valve" or jiggler is to allow air bubbles to vent out of the engine, and you should locate it in the highest possible orientation. If the thermostat gasket surface is horizontal, put it towards the front and if vertical, put it towards the top.
Now, I don't know, but I thought the smaller valve was just an early opening valve. I see there are 2 temperature markings. Although usually I've seen a larger spread; when dual thermostats are used it's a 180° and a 195°F, not 85° and 88°C.
Woohoo! Thanks for the info Darron!
Iain
"We don't stop playing because we grow old, we grow old because we stop playing." - George Bernard Shaw
but if you don't have the little water passage, how can you expect hot water to travel through the system to activate the thermostat?
TXMC: Drinkin, shootin, racin!