Monday I drove my car with the Commander monitoring water temps.

I was driving non-stop on a very hot day to GothamRacing to drop it off.

My linkage is screwed up and I can't get into 5th gear so I was in 4th gear all the way. I was driving with cruise control on and 65mph.

I reached 123C a few miles out of town and was really worried it would not make it. Good thing I had Evans coolant.

I noticed the fans did not seem to be running too fast.

All things Kan will solve. The motor he thinks has cracked corner seals. We'll see. Car ran great otherwise.

Well MPG was great, to me, considering 4th gear.

I got 17.7 with AC on. Then at night I averaged 19.8 and 20.0 with AC off.

Ken

 

123C? Damn I freak at 100C! My car has never seen over 101C! Even in the other days 98 degree weather!

 

7/04/02 Watkins Glen, 98F ambient, 129C 264F with Evans NPG+

 

Sounds high to me too.
Locally we hit 105 deg. F the other day. On a relatively stock car, with AC on, I saw 210-215 deg. F after a few gears with boost, but would drop back down quickly to 190 deg. F. or so after cruising.
50/50 coolant/water, stock thermostat, Fluidyne, Miata thermoswitch.

 

I think you needed to start worrying at 110-115C. You should never have seen that sort of temperature on the street, much less the highway. Something aint right.

 

You were running that hot BECAUSE you have Evans!

Evans will always run significantly hotter than water-based coolant in hot weather - it has much less heat capacity.

However, that should not be anything to worry about, since it won't boil as easily as water-based coolant.

 

I get kind of worried when mine moves over 93C on the highway..... It usually cruises at 89-90C.

 

**** i get worried when im going past 195f lol

and i havent seen anything that high this summer!! highest temp i seen so far was 185f during city driving..

 

I stay at a steady 86 C all the time.

 

I wouldn't be worried about boiling, i'd be worried about your rotor housings and water seals at those temps.

 

85-90C should be max unless you are WOT for an extended period. If its higher, you probably have some other type of problem like a leak of some sort, coolant low, or busted thermostat.

Water temps rising to at least 105-110C and not dropping back down no matter the type of driving or with use of fans indicates busted thermostat.

 

hit 127C going up a canyon on a hot day at 6000ft, i actually moved the stock gauge at that point! Been having cooling problems since i did the front mount. I recently had some shrouding made which seems to help force more air throught the radiator.

on 104F days I was seening 108C temps while crusing on the freeway at 80mph (sorry for the retarded unit non-conversion there) before the shrouding was installed. I replaced the thermostat and it did not seem to change the behavior. I also tried out a vented hood and the car would still get hot.

I am also running evans.

 

Unless you've reset it, I don't believe the fans even come on until 99C... so low 100's shouldn't be totally out of the question on a crappy hot day in traffic w/ the AC on.

At about 110 though, you ought to start paying attention, particularly if you aren't in a high-stress situation, like cruising down the highway.

 

129C after a hot restart.

The asolute max I've ever seen while driving was 114C in traffic after a hot restart with the A/C on and 112F temps. I doubt I'll ever see that again because since then I've opened up the area above the radiator fans with a RX7Fashion intake and a mini-battery.

I'm running Evans NPG-R. Just so you guys don't freak out it runs as cools as 87-88C on the highway in 88F temps with the A/C on and the fans on low.

 

I never see past 85 Celcius ... thanks to fan settings on the pfc

 

I hit 122 C right after my motor was rebuilt/ported. I was driving up hill on a hot day. I was running Evans NPG+ too. I think my stock-type radiator got clogged-up with all the engine sealnts used by the engine builder(my heater core is also partially clogged). I ended up buying a Koyo radiator and replaced the Evans NPG coolant. Now my temps stay around 85-86 C(with the fans set to come on at 86 C via the datalogit)

 

I've reached high 138c numerous times......

 

Cruising in 90 degree weather I hit about 91C, then with fans on low about 87C. This is with a front mount and no undertray.

 

????? How? Your car was blown after that right? If not I call B.S. My guage only goes to like 150! 138C is almost 300 degrees F!

 

I have a switch to manually turn on my radiator fans. Before I got my radiator underbelly shield I was averaging 240F temps on a hot day with only 1 rad fan working. I added the radiator unberbelly and keep my fans running at all times and my temp never goes above 180F. Once I add my 2nd fan i'll be running constant 160-170ish. Do you have the 2 fans and underbelly?

 

Nope, I've never damaged a coolant seal.

 

Sorry, you're wrong, I haven't reset or rewired the fans in any way, but I can still control them.

You can manual turn on the fans by switching the A/C on and off. Using this method, I can keep my temps between 85-90C. Running the fans also reduces heat soak (I believe). I am using a pfc, and the A/C only works on the (1) setting. 2, 3, or 4 is only fans. This "problem" is common to pfcs, however I find it to be quite useful. So I can run the fans without running the a/c or I can run the fans with the a/c on. Note: even with the a/c on, the water temps are much lower than they would be even without the fans on.

The IAT sensor in the intake manifold reads lower temperatures and rises in temperature slower with the fans on. In addition, running the fans after shutdown keeps water temps down between 95-100C max, without running fans, water temps can go over 105-110C.

 

I don't think i'm wrong.

The factory setting for the fans to come on is 99C. They will come on at lower temps if you load the engine, i.e.: fan, AC, lights. They will always be on if the AC is activated. I and many others have been pulling the AC relay to trick the fans on at the track. I also use the turbo timer to run them after shutdown... I also have them set lower on my PFC

The point was, you shouldn't need to be "worried" at 85-90C as someone suggested, because the factory wasn't "worried until 99C.

 

I guess my point was that you can controll the fans without resetting your factory's fans.

85-90 is a good range for temps because it is on the lower end of the 180-230 operating range. I wouldn't say that we are worried about it in this range. We just try to keep it within the range. Once you surpass 100C, there is a lot of heat building up under the hood, and it doesn't take much to reach unsafe temps. the margin for error narrows also. If you're used to seeing it in the 85-90 range, and if it goes 10-15C above that, you know something is wrong and have time to correct it. However if you operate in the 100-110 range, if it goes 10-15C above that, you may blow your seals.

 

I usually sit at around 84c. When hot or driven hard I maybe get 85-86c.