Engine Temp: Normal or Hot?

Carlwalski

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Hi guys,


Over the last few weeks I've been keeping my eye on my temps and I'm not sure if it's normal or not but I'm running around 90-95c which is around 200F, this is my normal operating temperature. It takes around 10-15minutes to get to this temp. I've done my research and most guys are running around 170, that's where I'D like to be!! :eek: To be honest, I never really paid THAT much attention to my temps or what was "normal". Having a ill fitting hardpipe (too long) recently let loose and sending my temps above 105c (the next line after 90 and it was climbing) due to rad fluids lost, antifreeze everywhere, heat/steam, what a mess. After that, it has me a little paranoid. Everytime I see my needle flick even a mm above 90 I watch it like a hawk.......it's taking the fun away from driving it being so paranoid lol. I have all the bolt on mods including Roe Racings 170 t-stat and Roes SCT tune. Still, my truck runs around 200F. I asked Sean why it would still be doing that and is there anyway to turn my fan on sooner? His response:


"Carl, 190-200 is normal in low speed driving and idle where the fan is having to work. I will explain how all this works.

1. When driving down the road, the air flows through the radiator at a rate faster than the fan pulls unless you really crank the fan up.
Your fan activates only when it gets above the preset point.

2. We spent time on the dyno and confirmed that we could lose up to 20 HP by driving the fan earlier and harder.

3. We determined an optimum point of temperature and fan activation point for the best HP and temperature.

4. If you want it on earlier, we can certainly do that for you, but it will be counter productive.

"


Now, I know Sean is the man at what he does so I'm not going to question is knowledge but I thought I should put it out here anyway. Is what he's saying true? I'd LOVE to look down at my gauge and see it sitting around 75c (170F) all the time. My oil pressure usually sits around 400-500 kpa (55-70psi). I'm looking at getting an external oil cooler with lifetime braided lines for safety to help take temps down. I also notice that if what Roe is saying is correct, then what about heat soak? If the fan is delayed and only comes on late, when I get on it/WOT from a cruising speed, the heat is full on and the performance lags. Any input is appreciated.




Cheers,
Carl



SRT10Gauges.jpg
 
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200 is about normal for a stock stat....I have a 172 stat and tune for the fan and my temp runs 180-190........170 is a little too low maybe...
 
So did you get your tuner to have the fan come on sooner? I know you're running a Roe, so even your supercharged truck runs cooler than my 170 t-stat bolt on truck lol, you can see why I think mine is running a little hot. :( Thanks for the input Larry!
 
Yes, my fan comes on sooner....but I still stay in the 180-190 range......though it will go to about 170 on a cold day at steady speed for maybe an hour or more......
 
May I ask who tuned your truck? Two guys seem to stand out in searches, Roe and Torrie.
 
Is it not summer down there??? That would account for higher temps than here in the USA. Even with a 170 tstat it will still run hotter .The 170 tstat just opens sooner.

If you want the fan to run when you want it to check this out:
 

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Carlwalski said:
May I ask who tuned your truck? Two guys seem to stand out in searches, Roe and Torrie.

Torrie did the final tune.......and just a FYI...Roe does his own custom tuning but the original tune for the Roe SC was developed by Torrie....
 
includemeout said:
Is it not summer down there??? That would account for higher temps than here in the USA. Even with a 170 tstat it will still run hotter .The 170 tstat just opens sooner.

If you want the fan to run when you want it to check this out:
Tis is true, but we don't get "too" hot down here, usually around 75F to 90F. But I guess that would help increase temps, still, I would have thought 200F is still a but too toasty. It gets to these temps even on mild, overcast days. Thanks for the info on the manual override, I think for me personally, I'd rather just have it engaged via a tune at a set temperature. Wouldn't turning the fan on at will throw somethings out of whack? (fan speed vs something? lol).
 
Carlwalski said:
Tis is true, but we don't get "too" hot down here, usually around 75F to 90F. But I guess that would help increase temps, still, I would have thought 200F is still a but too toasty. It gets to these temps even on mild, overcast days. Thanks for the info on the manual override, I think for me personally, I'd rather just have it engaged via a tune at a set temperature. Wouldn't turning the fan on at will throw somethings out of whack? (fan speed vs something? lol).
Just slows the steering as Stingray said, but in traffic or at the strip you can cool the truck down real quick like:D Wifey's runs about 200 or so also.

Your truck is NA and the tunes for a FI engine are a bit more conservative, yours is probably a bit leaner than in the FA ratio than a FI engine.
 
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the fan is controled by the ecm via the ps unit, an aluminum block does like higher temps so lowering you will loose a "couple" hp, but nothing you will notice.
the only way to cool it to where you want is to have the pcm or the sct flashed to have the fan come on earlier, installing a 170 degree thermostate does absolutly nothing for performance other than takeing longer to warm up
 
Thanks guys!


Moparracing - That is cool, I have looked at additional fans, the fan you have, is there any cons to running that ALL the time? Can it do any damage if I wanted to run something like that 24/7 when driving it? I probably wouldn't, more so in traffic and WOT driving but I'd like to know if it could be done and if so, comfortably, no issues what so ever? Anyone know?
 
Carlwalski said:
Moparracing - That is cool, I have looked at additional fans, the fan you have, is there any cons to running that ALL the time? Can it do any damage if I wanted to run something like that 24/7 when driving it? I probably wouldn't, more so in traffic and WOT driving but I'd like to know if it could be done and if so, comfortably, no issues what so ever? Anyone know?
i just have mine on a on/off switch for the track, but you could certainly switch it on with a temp switch if you wanted..... if you were really concerned about running alot, you'd probably want to replace your hydraulic fan altogether with an electric.... tony or justin, i think, has an application for that....... :)
 
its not good to run it continually , at hwy speeds it will actually run hotter by retaining the heat, since the incomming air is traveling faster then the fan can turn. ;)
 
Thanks for the info eveyrone, good to hear others opinions and info. :)

I'll continue my research. One way or another, I WILL get the temps down. ;)
 
One more Carl...

Sean has tuned mine since the start years ago...I do have a 170 thermo...but have not changed the pcm to turn the fan on sooner.

My constant temps are 200-210...in traffic, but never goes above 220. We tested on my truck and engaging the fan is nearly as draining on horsepower as having the air conditioning on!!! The air conditioning will pull about 15% of your horsepower.

Reference heat soak...our pcm's pull timing rapidly as intake temperatures rise. This is the "heat soak" issue...it is not a physical thing...rather the engineers have added the safety margin of pulling timing as the IAT sensor temps rise to prevent engine detonation due to higher temperatures.

Some of us with superchargers have added the "Roe IAT Mod" to fool the pcm about temperatures, which avoids the pulling of timing under high temperatures. But we take additional precautions like adding water/meth injection. The modification is a five minute process of adding a 5.6 ohm resistor in the return wire that sends the temperature reading to the pcm...the 5.6 ohm resistor "lies" and sends a reduced reading to the pcm to keep the pcm from pulling timing under high temperature situations. To do this you need a wonderful tune and you need to be very cautious about 'hot lapping' at the strip...but in normal conditions it assures that your pcm is not pulling timing for the sake of safety.

One more perspective...my supercharged daily driver is an alum engine at 556 hp and 551 ft lbs tq. It runs at a constant 220 degrees, and is designed to do so for better performance...as Tony says Alum needs a little more heat for best performance.
 
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Thank you Prof, good info mate. ;) I have always thought heat soak was just the normal "heat soak". Where temps in high degrees drain and sap power, like if you leave a battery in a steel container for a period of time, the heat literally drains the power from it. I guess heat soak can have different meanings, now I know which one the majority are referring too. I will be starting a new topic (to gather more input) on the factory air deflectors in the grille area, also known as (from what I have found) "air blockers"?? Anyhow, thanks again Roy. :)
 
hey Carl

have ya checked out the Evans coolant product???

a good thread on it here & their web site is very informative @ evanscooling.com
 
Hi ZCx, no I haven't I've heard "a little" about them in car circles but nothing sufficient. I found the 7 page thread on it here and from page 1 to 7, no one (except 1?) guy put it in but hadn't actually run it. For $300 and unproven I think I'll look at temp drop solutions elsewhere lol I thank you all the same for your input, it all helps.


I'm looking at large coolers and came across this Perma-Cool fluid cooler w/fan and they state: "Reduces fluid temps up to 95F", that's a good start but do you think that claims a little BS? from 200 to 105????? I wonder if these temps were taken after the addition of a custom rear tray ice box setup and 50" intercooler setup lol. Having said that, it does flow 900cfm and even if it did HALF of what they advertise, it's still a massive drop. From 200 to 150F - hell yeah!! On paper the dimensions sound big but removing the air deflectors and custom brackets/hoses will make things possible, I'm sure of it.

http://www.summitracing.com/parts/PRM-12311/



:burnout:
 
To fit the lifetime braided oil lines like tony sells, I'll need a cooler with -8AN male fittings, correct? Not the NPT stuff?
Never been good with the AN style fittings arrrgh!!!
 

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