PhoenixDownVII

My FD is essentially stock. Some main hoses/clamps replaced, lightened flywheel, aluminum AST, High-Flow Cat, M2 Dual exhaust...

I normally see 180F if I have some good air coming through, but today as I went through town (a lot of stop and go from light to light) my temps were up to 195 going higher....

I know and understand the AC-3 quick resolve, it works great in that traffic. However, it's also to my understanding that, besides that, the fans won't turn on until 212-215F water temp right?

So given, tomorrow I may be autox'ing my car, I really don't want to use the AC-3 while racing because it puts more strain on the car, blah. Should I not fret about the temps during my run, and just have the ac on before and after?

Brent 94

iTrader: (1)

i'm pretty sure turning on your AC will make your car hotter, not cooler, because the engine has to work harder/ eats more gas and what not. I could be wrong but that was my understanding. I thought that turning your heat on would cool the engine down because the coolant is being cycled through which makes the air blowing through your vents hot. Correct me if i'm wrong.

PhoenixDownVII

Yes and no. While running the AC definitely makes your engine work "harder", the trick in our FD's is that when the AC is on 3rd power it automatically kicks the radiator fan on high. So despite the load on the engine, my Coolant Temps drop dramatically. All thanks to the fan being on.

I know a fan switch is in the near future, but until then, it just seems like a tough thing to overcome. Not sure how high is too high before I should just stop.

Yes, blowing hot air out the vents help relieve engine temps as well, too

rynberg

You'll be fine. Just open the hood after every run. You can also pull your A/C relay (black relay box by intake/intercooler -- under stock Mazda plastic cover). This will enable you to run the fans by turning the A/C "on". The A/C won't actually be on but the ECU thinks it is and turns the fans on. Great tip for auto-x or tracking the car.

adam c

iTrader: (2)

Easy fan mod link:

http://www.fd3s.net/fan_mod.html

Be sure to turn the switch off when you shut down the car, or it will run down your battery