82c Thermostat Fan settings

[L67PSI]

Yes, you are probably right. I'm using a XU6 enhanched bin and they were the settings it had.

The standard L67 thermostat is 91 degrees.

With the standard thermostat being 91 degrees the differences are
Low Speed Fan On = 99.50 - 91 = 8.5
Low Speed Fan Off = 98.00 - 91 = 7

High Speed Fan On = 101.00 - 91 = 10
High Speed Fan Off = 99.50 - 91 = 8.5

So if you drop the thermostat to 82 degrees and add the difference you will get
Low Speed Fan On = 82 + 8.5 = 90.5
Low Speed Fan Off = 82 + 7 = 89

High Speed Fan On = 82 + 10 = 92
High Speed Fan Off = 82 + 8.5 = 92.5

Again I wouldn't really bother unless there is an overheating issue but the differences have now been worked out for you to use if you wish.

I'm fairly certain the stock tune would be low speed on 104 off 99.5 and high speed on 107, off 103

[MAGP]

I'm fairly certain the stock tune would be low speed on 104 off 99.5 and high speed on 107, off 103

I just did the math with the info supplied by the OP, if the number are incorrect he can get the correct numbers and then do the math again.

[L67PSI]

Thanks, I'll give these settings a go.

The whole point of fitting a cooler thermostat is to make the engine run cooler.

I have mine set low fan on 88 off 84, high speed fan on 90 off 86.

If you set the on/off temps really close together than the fans will cycle on/off constantly.

[Holden202T]

yep I agree i'd change the settings to match the difference in the thermostats.....

if its a streeter i'd not want it too much below 85-90 for economy and such but if its a weekend toy then you can go a bit lower....

depends on the fuel too, I personally have found my race car actually goes better with higher temps but this might just be a methanol fuel thing, but could be the same thing for E85 if you use that, would require some R&D though.

[immortality]

The engine should run at the thermostat temp when there is enough airflow through the radiator, the thermofan is only there to supplement that airflow when traveling slow or stationary.

If you want the engine to run slightly warmer than you need to run a hotter thermostat.

I find with our VX that the low speed fan keeps the engine at about 84-86°C when stationary or in stop start traffic. Now that I modified the CAI the engine temps are dropping to thermostat temp once cruising I even fitted a larger WP pulley cause it was pulling the temps down to far.

What I can't figure out is if GM wanted the engine to run at 91°C why let it heat up to 104°C before turning on the thermofan?

[Holden202T]

I think the whole idea of it is that the thermostat should do the majority of the work if the car is moving, then the fans are there as a backup before it gets too hot to cook the motor ..... having the fans on draws power which loads the alternator, which effects performance and economy, so the later you can leave it the less time its on and hence better figures I think this is also the same idea behind high and low speed, enough to cool in most cases, then high speed is there for the really hot times!

[pman92]

Yeah I would say they would want to wait as long as possible before turning the fans on to reduce the electrical load.
Also when sitting stationary under no load the hotter temp may make the engine run more efficiently? Less emissions while sitting at the traffic lights?

[immortality]

Yeah, I get that bit, it's just that heat soak is a bitch.

[vlad01]

Yeah I would say they would want to wait as long as possible before turning the fans on to reduce the electrical load.
Also when sitting stationary under no load the hotter temp may make the engine run more efficiently? Less emissions while sitting at the traffic lights?

yep, more efficient to run an engine hotter as that reduces quenching of the combustion near all of the surface of the combustion chamber/cylinder wall. Obviously too hot and volumetric and mechanical efficiency starts to go down.

[L67PSI]

Thanks guys, i will give these suggestions a go.

A question regarding the high speed and low speed fan. What are the differences between them? Are they different speed motors?

Thanks