gerald m

^^^ Well I ran a successful general service garage for 18 years and I have opened up hundreds of thermostat housings to find , thermostat stuck open , stuck closed, halfway open .and laying in pieces . and there is just no way anyone can operate a vehicle summer or winter without a thermostat to maintain CONSTANT temperature. In summer at moderate temperature and moderate speed it is possible to keep things more or less under control. In the winter there isn't a chance in hell that anyone will have a warm vehicle without a proper thermostat of some kind to maintain. What happens if you take the house thermostat off the wall ??? What happens if you turn it up to the top ??? I'm not just relating to the Mazda Rx7 rotary but every dam internal combustion engine in a car . Even the VW air cooled had a set up ( not that it worked worth a **** )to keep the engine at a constant temp . Without the thermostat we would all have snot sickles hanging on out nose in the winter . Even the Air Conditioning units have a thermostat controlling how much cold air the unit produces. Theory my butt 45 years of working on vehicles from semi trucks to little cars is what I;m talking about . Anyone that doesn't think thermostats do a much needed job is probably just inexperienced (Like I am new to the rotary) and just doesn't know any different .ROTARY RESURRECTION your right and you know it Gerald m.

eage8

iTrader: (9)

Stant makes 2 different types of thermostats... the crappy ones that you can get in both 180* and 195* with no jiggle pin (part numbers: 13978 and 13979) and a decent one that looks exactly like the mazda OEM one with a jiggle pin... (part # 48438)...

get the decent one and you'll be fine. I've never had any issues with the nice ones in any of my cars, the crappy ones are crap though.

scathcart

I agree that it makes sense to run one on a street car. As well as most race cars. I never stated otherwise, merely that if you are going to gut, or remove it, you need to block the bypass.

I stated that slowing coolant flow reduces cooling capacity. This isn't theory, this is fact.

However, there are times during racing where simply removing the thermostat and blocking the bypass can keep your operating temps in check. While I don't recommend this, the increased coolant flow by removing the t-stat can occassionally mean the difference between staying on the track, or skipping laps to let the engine cool down.
There are better ways to increase flow and keep a thermostat tho. Machining a series of 1/4" or so holes in the thermostat outer casing helps flow, although it makes the engine take longer to heat up. Increasing the system flow with a properly designed single pass, crossflow radiator, modifying or replacing the exsiting water pump, under-driving the waterpump at higher rpms to prevent it from cavitating, or replacing the pump with a constant speed, high-flow electric water pump will all increase coolant flow and increase cooling capacity.
Outside of coolant flow, DUCTING and radiator size will aid cooling.

Michael Hernandez

Had the same issue. OEM FTW!