V-AMG

Hey gents,

I keep reading about the 10C cooling mod via STAR/SDS/xentry, etc. but I am not able to find all the data I am looking for before I proceed. First time you do this, when you access the correct screen, the top right will read 12C (see attached photo), is that correct? My questions are:

1. What value does that 12C actually represent? What is the temp at which the lo/hi speed fan gets turned on in stock form?

2. The instructions below say that making the number more positive will kick the fan on sooner, and more negative numbers later, yet all that ive been reading states the opposite...

3. Guys call this mod the "-10C mod". Do you actually lower this value from 12C all the way down to -10C? So there is a 22C difference in when the fan will come on?

4. Hypothetically, can I just lower it down to, lets say 0 instead of -10C, and have the fan come on 12C sooner than stock rather than 22C earlier if i was to go down to -10C?


Any clarification on this will be greatly appreciated!

Mackhack

Don't do it. There is a reason why the threshold temperatures are set at that specific one.

There is absolutely no advantage by doing this. I'd say there is rather a disadvantage by doing so.

V-AMG

Mackhack, i can see the premature wear of the fan being the only real disadvantage. Is there something else i am missing?

I have read that people reported a 5-10*C temp drop on their data loggers. With that in mind, I do have to say that for the price of 'free', lowering my coolant temps is very tempting.

I am only thinking of lowering it 5-6*C.... that's given that I can figure out what i need to correct the value to...

Mackhack

Your engine, your material, you risk.

I'm not an engine expert by all means, but just common sense teaches me not to touch certain things and I do a lot of modding.

Also keep in mind, your fan doesn't necessarily cool anything while driving. It's more for after you're done helping to cool off the engine. Your engine and coolant gets cooled through wind while driving.

Ls1toAMG

If it's hot and I'm running above 86c I will turn the fan on high through climate control. The car runs harder and better at 82-84c than 92c. You can feel it

Mackhack

Proof other than subjective feeling? I highly doubt it since we need cool air for the kompressor/intake. And air for the intake is not cooled down by the engine fan.

MTV10

Don't even bother.
The fan coming on all the time is incredibly annoying

1970gsx

The fan noise is horrible all the time. The fan can't cool the car below the thermostat setting, so it will run continuously trying to do so. I did for about an hour and changed it back to stock.

Mackhack

Glad to see some smart people joining this thread

V-AMG

How much lower did you set your temp? Full 10*C?

Also, when you did so, what was your base value and what did you change it to?

This is not a permanent change so i want to try it and if i dont like it, its easy to change back...

Yacht Master

To change engine temp you must change the thermostat, at one time member PTE made the 180* F thermostat.
Many members here that had SC insulators (thick inlet gaskets) split IC cooler, 180 Thermostat and 10* mod would get CEL engine too cold.
Fan noise was a complaint too.

Mackhack

Never change a running system!

V-AMG

That's understandable. On the other hand, im 100% stock, and wouldnt mind a little extra breeze in stop and go traffic. All that the fan does is replace air that moves accross radiator while the car is in motion. Reducing the coolant temp in the radiator by 5*C wont be a drastic difference, but once again, it is very simple and i dont see why not introduce slightly cooler antifreeze back into the engine. I understand what a tstat does, so i know i wont be recirculating liquid until a certain temp at which the tstat opens, but if i can reduce the engine bay temp and possibly engine temp by a few degrees just with a parameter change...i'll take it, count me in.

What im getting at is, im not concerned with the question of whether to or not to, im curious about the how to. I'd like to know what the base value is and what the changed value needs to be to kick the fan on a little sooner.

Thank you

1970gsx

It sounds like a hover craft if that is what you are going for.

SICAMG

1-The fan plays a huge roll in keeping the engine cool while you are moving at low speeds.
2-Disconnect it and see how high the temps will go...and it will get real hot in the summer months as well.
3-Most cooling systems will not continue to run after the car has been turned off.
4-A fan running a little faster than normal will really help with heat soak of all engine parts and that goes for the supercharger too.

Mackhack

For god sake we are in America with a speed limit of 65 mph. Let's take into consideration that we all speed a little bit for a few seconds here and there. We don't drive Autobahn speeds of 200+ mph for extended periods of time where cooling and more cooling really would help.

This starts to become a joke thread IMHO. LMAO!

V-AMG

SICAMG brings up my point again... the fan is only useful at low speeds. At 65mph or at 200mph, the fan will not be turning on, and even if it did, it certainly wouldnt contribute anything with ambient air passing over the radiator at +65mph.

But if it did, i would keep it on all the time to propel me forward, haha

SICAMG

Thats perfect !!!!!Keeping the fan on creates a constant suction that pulls the car forward thus....increasing your speed. Outstanding !!!!

bzmith

V-AMG - I'll try to answer your question as I have done this to my stock 03 E55. I changed mine to +10 and my fan starts sooner and does run more, but since I did it for the same reasons you are saying I don't mind the sound of the fan, as when it comes on, I take solace that I am helping the engine run slightly cooler. The thermo-stat controls the engine temperature to specification, so there is no worry that my engine will run too cool.

It s easy to change, so I say go ahead. I was able to find a pretty good DIY explanation in the DIY with STAR thread on this site.

Good luck and happy experimenting.

Ls1toAMG

Like everyone has said. The thermostate will open at a set temp. BUT with this mod cooler water will go into engine when it opens. Over all the engine will come to temp when it opens, but most of the time the engine will run cooler. In the summer heat mine goes from 92c to 84c. Less heat in engine means less heatsoak into the supercharger cooling system. It is without a doubt effective. Try it one time and you will know.

LAsunset

....wrong post