BigRed has ran the FD without a thermostat and noted that the temp stayed in the same spot.

Is the stock temp at 195 or 180?

Any harm if I drop that to 160F?

I heard that the higher temp works better with emission devices........

 

I never used a lower temp thermostats because i couldn't find one for FD. There is one for FC. I would think there is no harm using lower temp thermostat other than taking a longer time to warm up ur engine (wasting more fuel)

 

I used pettits long ago. I think it was a 170deg. It indeed took longer for the car to warm up. With the stock temp gauge i couldnt tell weather or not the car actually ran cooler. I ended up putting the stock thermostat back in when i replaced the engine.

 

Anyone else run lower thermostat or no thermostat at all?

 

I run the pettit deal which i thought was the miata thermostat??? My temps on hot days seem to stay around 88 to 96 with normal to hard street driving. Not sure if this helps.

 

so do some of the Mazda models have interchangeable thermostats?

 

I'm not sure what you mean by that...

but I also have the pettit thermostat...

170 degrees...

at nights my temps on the PFC is 76 on the nose.....

but with my 99 spec front and dual oil coolers I can see the temp drop below that.

During the day, 90 degrees here in Dallas on the highway, I get 86 degrees C....

Car is still in the break in so don't have track numbers yet.

It definately takes the car a long time to warm up....

 

I had the pettit 170 thermostat.....couldn't tell any difference other than taking longer to warm up. I didn't have an upgraded radiator at the time but with it opening up sooner I would like to think it would keep it a tad cooler.

Tim

 

at 170 does the FD stay in "warm-up" mode? or does it eventually warm-up and run the correct A/F ratios?

 

I don't know if any other mazda's have interchangable thermostats like the miata. And for that other question of yours batman I have no clue.....I was no help in this thread whatsoever I just wanted to be part of something....

 

i dont run a thermo stat...takes forever for the car to to warm up....

 

ok please don't flame me but how do you check if the FD is still in warm up mode?

And I think you can change this with the PFC correct?

<---I have the PFC

the car, untuned, runs alittle rough when first starting the car...once the car hits around 67 degrees C on coolant temps, the car seems to run just fine...

 

do u know what temps ur getting obviousboy?

There has been some concerns about newer cars overheating since they need the thermostat for proper flow.

 

The 3 major power loss is chemical efficiency (turning gasoline into energy or the combustion process), thermal efficiency (converting thermal energy into mechanical energy or maximizing the cumbustion process) and mechanical efficiency (transffering mechanical energy to the ground or transmission power loss).
Modern day combustion engine requires to be at a certain temperature to maintain thermal efficiency. The temperature is around 195 to 210 F. By lowering the engine temperature with a different thermostat (especially one as low as 170), you are actually causing the engine to run in a less than efficient range. If you want to prove this to your self, put the car on the dyno with a normal thermostat and switch it out with the 170. Do a couple of runs with the car fully warmed up and see what happens.

 

could u tune for this?

years ago when i had my FC N/A I pulled the thermostat out.

I noticed more low end power. The car felt like it was just warmed up in the morning everytime I drove it. Not that "heat soak" feeling.

 

Trex,

I agree and thats why I was thinking about switching to Evans to get my temps back up...

However, with the lower thermostat, the car seems to be able better able to keep the temps lower....

I know, I know....once the thermostat temp is hit both kinds are both open...however, just an unscientific observation. After I installed a koyo my temps remained unchanged on the PFC, even after putting a downpipe in.

After placing the thermostat, the car would have "lower temps" then before...eh...maybe I just had a bad stock thermostat :P

 

well sometimes they seem to cold...my car hasnt really been on the road much..though the one night i took it out. it was liek 75 degrees... at cruising i was getting 168-175 on my digital water temp (tapped into the water pump housing)

im also ducting my radiator and intercooler...so basically my radiator sees every drop of air that hits the front of the car..

it seems to cold though....

 

i have a stock mazda thermo from malloy. i'm pretty sure it's 180* since i have yet to see my temps go over 89*C with a fmic and pwr radiator

 

Stock t-stat is 180 degrees. However, the stock ECU won't let the car run at its full potential at that temp. The car runs much stronger when it is closer to 200.

 

Adam,

I remember reading that alot on the forum...would it be any different if you had an aftermarket ECU where you could adjust the fuel?

Or is it just the 13b in general that likes to be around 93 degrees C (200F)??? What coolant temps do the NA FC's run?

 

I'm seeing an average of 85C on my PFC commander.

 

WOuld the FD pass smog (meaning that it runs normal A/F ratios by being in the warmed mode) if the temps are 168-175 degrees?

Somehow the engine seems to be stronger for me when it's just slightly warmed up.

If it's heat soaked there is some loss in power via butt dyno.

 

A lower thermostat is not going to lower coolant temps. The only thing the lower thermostat is going to do is take longer for the engine warm up. Once warmed up the car will run just as hot as it did before. The thermostat has no control over coolant temps; only the warm up period.

It is a bad idea to remove the thermostat completely. With no thermostat there is no restriction in the system and coolant will flow too quickly. This means the coolant won't spend enough time in the radiator and cooling will actually be reduced when pushed hard. If the car is for racing and has no need for a thermostat then you just add a "washer" in place of the thermostat or you gut the stock one. Both of these will still provide a restriction which will slow the flow of coolant.

The stock ecu will not even open the double throttle until 180F I believe it is. I never run my car hard (street, track, anywhere) unless I see at least 180 on the temp gauge.

 

doesn't the PFC have an adjustment for this?

 

I dunno. But if it's established that you don't want the engine to see full boost until 180F why would you want to?