has anyone monitored coolant temps on the S2
 

curious as to how they are doing compared to the S1. especially in a low speed enviroment
if anyone has can they please specify where they monitor from and what the ambient temps where??
OD

damn---guess no one is????

I was hoping someone would post also. I want to get some gauges set up to do this, I know there is a spot for an oil temp gauge on the s2(maybe s1 as well?) so no modification needed.

Missed this thread, yes I am monitoring coolant temps. I have an adapter on the upper radiator hose. Basically I replaced the OEM one with one of the adapters that prosport offers. Only thing is that you wont read anything until the thermostat kicks, which is at like 140F i think.

~70F Day
Street Driving: ~190F-200F
Highway: ~170F
Idle: 210F+

~24F Day
Street Driving: ~170-200F
Highway: ~140F
Idle: ~180F+

No spot for oil temp, but there is an oil pressure port. Oil temp on the S2 is best read with a sender+adapter into the drainplug of the oilpan

+1 to the above post. My coolant temps are comparable. However I'm still right around 160 on the highway during the warmer weather we've had.

Thanks Guys!
so the S2 is not running any cooler than the s1--it seems?
That is interesting. 200F seems to be a good running temp for this engine but the S1's seems to not have the capacity to keep it there-- low speed/ high ambient temps+ ect 220F+ by some.
Lets see what the summer temps do?

Yep thats what I am waiting on. If we have a summer like last year here in CT, I should see some ambient temps of around 100 - 110F. I expect my street temps to hit about 220ish and highway to linger around 180ish

My S1 runs at 208 to 212 farenheit at 98 F ambient temp in stop n go traffic single oil cooler, no cooling mods.

AH, not sure what this is getting at..has all been posted before..

1. the S1 and S2 has the same Thermostat...so....
2. the S2's have a larger 120W (same) Fan Motors.
3. the S2 has a 3 Speed Cooling Fan set up the S2 has a 2 speed-stage.
4. the S2 has changed Water pump.
5. the S2 has a revised Radiator.
6. the S2 has a better oil cooling/pressure set up.

If one does not own one of each Series how can they really compare??
Same outside temps and engine speed and equipment to measure coolant temps.

As I see it the S2 engine does not run any cooler, but it's efficiency would have improved with the updated Water Pump, Fan Motors, Extra Fan Speed, upgraded Radiator.

Obviously Mazda made these changes for a reason in S2.

Thermo kicks at 140f?

Those SII's get ready for heat load early.

I don't run at 24f, but at 49f the lowest temp I saw while hwy cruising was 178F, and I'm pretty sure the thermo opens at 180f from the way my 07 6spd auto temp changes when it hits 180.

Don't mean to thread jack, but the highest water temp my 07 SI got was 229F on a 95 deg day balls to the wall on a HPDE track.

I do own both. But my S2 doesnt have a temp gauge.
All the earlier discussion about heat being one of the major things that helps to cause the SI early engine failure is why I am wondering about the S2 which is NOT having early engine failure.
Maybe heat is not the problem after all?
Maybe it was the lubrication that was the main thing?

Yep, I actually double checked my gauge readings to those coming from the ECU and they are pretty much spot on which is reassuring. This is going to be my first summer with the gauges installed so we should get a better understanding in the next month or two. Today though coming into work I was easily rocking 180F driving through parking lot at 68F ambient.

I am more interested in seeing what the oil temps look like.

i have own both s1 and s2 and have been able to keep track of some numbers from the summer here in vegas

S1: 100 deg+ according to ambient
street driving= 202-230
hwy driving= 200-215

S2: 100 deg+
street driving=190-210
hwy driving=180-198


cruzing on highway i never seem to go over 200 deg even on a hot day over 100+ with the s2 unless going up a hill or taking it to redline.on the street it will be over 200 but once i enter hwy temp will drop down below 200 deg.

forgot to mention that my s2 idles alot smoother than my s1 did in the heat.

Thermostat's (OEM) are exactly the same part for Series 1 and Series 2 RX-8's.

Initial-opening temperature....80-84C (176-183F)
Full-opening temperature.......95C (203F)
Full-open amount.................8.5mm 0.33 inch or more.

OEM Coolant Bottle Pressure Caps are the same....Cap Valve Opening Pressure 10.63 -14.98 PSI.

Cooling Fans..( Series 1 has two Fan Motor Speeds, Series 2 has three Fan Motor Speeds and larger Motors )

Less than 207F* COOLING FANS OFF S1 and S2.
More Than 207F* ON Low Speed S1 and S2.
More Than 214F*-226F* ON Middle Speed S2 ONLY, More Than 214F* ON HIGH SPEED S1 ONLY.
More Than 226F* ON High Speed S2 ONLY.

AFTER COOLING (Engine Stop)
More Than 230F* FANS ON High Speed S1.
More Than 230F* FANS ON Middle Speed S2.

ECT Sensor* (in Water Pump rear housing) Failure all Fans ON High Speed S1 and S2.

Besides, the cooling fan updates, were there any changes in the water pump and system capacity for Series-2 ?

Minor....

Water Pump is slightly different, plastic impeller, O ring Gasket.
Radiator takes about a cup full (200 mils) more coolant than a manual S1.
S2 Auto Radiator coolant capacity did not change until around 2010MY (from memory) to same cc as S2 manual.

Without any doubt the major change in the S2's cooling efficiency was the extra and higher Cooling Fan speed for extreme hot conditions...like in stop go traffic...AC on...or above 226F (108c).....or around the 100F outside temps and or with AC on.

This is cool information. I don't have an S2 but drool over the thought of one daily.

I actually set my temps higher than OE on my S1 with the Evans NPG-R coolant

It only ever sees those temps when not moving, once the car has air flowing through it the temps immediately drop, even under WOT conditions

Of course this is NA, the problem with using a SC such as OD is that the frictional losses substantially load the oil and radiator cooling systems

Very interesting - I have not heard of that before. http://www.evanscooling.com/products/coolants/npg-r/

How did you raise your temps? My car ran too cool all winter and built up all kinds of crap in the oil pan and elsewhere. I wonder if your changes for performance purposes could help a more pedestrian issue.

Not sur because I've never had that problem, but then my RX8 doesn't see daily street use