Thermostat identification

[350matt]

I know I have mentioned this before but thought it might be an idea to show the measured differences between a genuine Mazda stat (PN N3H1 15 171) and a 'good' aftermarket one
In this case gates unit

As you can from the photos the mazda main port is 31mm across whereas the gates one is 26mm

So 30% SMALLER in area as well as not being off centre so the better match the port in the engine.

Our engines do not like being overheated so please fit a stat with the right size port

[warpc0il]

As is so often the case, many aftermarket parts sold as "performance" or "upgrade" are actually a degrade to the Mazda OEM.

Thanks for providing the clear evidence in this case.

[New Duke]

I've got a Gates one. It has run hotter (measured) since I replaced the Mazda one. Handy to know why. Gonna rip it out and fit another Mazda one, cheers Matt.