Excellent.
So far, my maunual disable for highway use has worked fine.
I have a simple ON/OFF switch interposed between the relay ground and the thermoswitch and temp at speed is fine with no fan at all.
Even the short amount of time needed to pull off and back on the road for a fill up doesn't raise temps.

Obviously, a completely automatic setup would be better, but this has been fine for the short term.

 

That fill-up story is more confirmation that I am on the right track. I have been looking at more oem setups. All I have seen measure the temp at the return to the engine. My sensor at the inlet side of the radiator makes the fan run too early and cycle too often. If I set the temp higher so this does not happen, the engine runs warmer than I want.

 

My sensor kicks on at @180° and doesn't seem to cycle at all during city driving- I think it's on all the time (hard to tell cause I can't hear it)- but I don't much care since the resulting temps are very stable.

I was mostly concerned with fan use on the highway simply from a mileage standpoint.
Unfortunately, so far on this trip I've had to the use the headlights all the time (lots of rain), so I haven't gotten the results I was hoping for.
Later today I make the 350 mile jaunt from Chicago to Traverse City and conditions are much improved, so we'll see.

 

So, I have been playing around (What?!!!) with my efan setup. I installed a VDO temp sensor in the Bottom of my Radiator in the OEM spot. I have been watching the RETURN coolant temps, trying to determine the right temp setting on my adjustable fan thermostat. My goal is to determine the correct temp setting by monitoring the coolant after the heat rejection occurs in the radiator. This has been going on for a couple of weeks now.


I believe that the following is true:
A.) If the fan temp is set above the initial coolant thermostat opening, ie. 185* and
B.) the return temp stays below the initial thermostat opening temp, then
C.) I have sufficient cooling without
D.) excessive e-fan running. (excessive alternator/fuel consumption)


The temp controller measures the coolant at the top hose to the radiator. Fan is always temp controlled on *low* speed.

If I set the fan to run on low continuously, the return coolant temp will hover in the 160* range all the time. This is city driving, parked etc. It slowly rises up to about 185* on the highway, 55-60 mph and stays.

If I set the fan temp controller to 215*, the return temps get very erratic. The temps range from 185* to 250*. Yes, I said 250*. Evans Coolant, Baby! The temp is obviously overshooting. The highway temps will hover around 195*.

If I set the temp controller to 195*, the return runs from 170-185*. No overshooting, no overcooling etc.

This testing was done with day temps in the 80* range as we have had over the last couple of weeks here in the Dallas area.

 

...if I run the A/C, my setup runs the Efan on High Speed. Low speed is overridden. Whatever the setting of the thermostat, the fan runs on high.

The temps will drop to 160* and STAY there. I have even watched with the radiator cap off. The coolant thermostat will actually completely close. When this happens, the coolant will stop rushing past the open cap. Pretty awesome to watch.

 

nice thing about controlling your fan with a standalone is that its much more precise. I wonder if there is a better temp controller you can buy?

I have mine set to come on at 190 and it comes on right at 190, on the highway my car can run without the fan coming on if I drive normal and dont boost alot.

I prefer to have the engine running with its thermostat open all the time, which for me is 180 degrees.

 

Of course there is a better temp controller. I am also curious regarding the location of the temp control sensor. This data collection is part of the process to determine what I need for my N/A.

Obviously, I am not going to a standalone just to control my efan.


What is the hysteresis on your temp control with the standalone?

 

if your asking me where my sensors are I have 2 in the waterpump housing- one for the Wolf and one for my Autometer gauge, the wolf obviously tells the fan when to come and off.

I also have the stock sender in its stock location.

I dont have a sender in the radiator though.

When my vert was NA I had the stock cooling system set up and that thing never budged over 180 degrees even in traffic with the AC on, what is the reason you are going through all this trouble again?

 

I think that those numbers are the total draw on start (takes more to start the motor than run it once it is up to speed).

And remember to blow a 40 amp fuse you really need to run 45 amps through it for more than a few miliseconds.

 

and thats when the motor is brand new

 

im curious if the fiero fan is any good

 

http://www.powerenterpriseusa.net/pr...switch/fsc.htm

 

This afternoon I am drilling the water pump for the permanent temp switch and for the temp sender.


So your stock cooling system never allowed the thermostat to open? Remarkable.


Air conditioning+ cooling in one of the most hostile environments in the US. We have most of the heat of Arizona and most of the humidity of southern Florida.


In Dallas October gave us 19 days over 80 and two more days over 90*. This is the 7th of Nov. and we have had 5 days over 80* and only 2 days under 80.

August and July we had 25 days over 100*, only 4 days where the high was under 90 and 24 days when the lows were 80* or above.

In Texas, it probably would have run about 182* and started opening the thermostat just a crack...

Rob, excess is what this board is all about. And by the way, later I will be measuring the static pressure of the Taurus fan vs the static pressure of the Mark 8 fan. Not trouble, just knowledge. I'm in the trial stage of a retrofit efan kit for 929 Porsche, working with a friend who is in the business. Much of this is really about that project and my RX7 is a test mule-with really, really great A/C.

 

I've got 2" of scars and 1500 dollars in hospital bills (27 stitches) proving that's a damn good piece of advice.

 

I was only asking to see why the over thinking, and you answered so Im good!

I always had a stock Mazda thermostat in my car, matter of fact I would change it every spring- dont ask me why, its just something I always did.
I think if I was driving on the highway in 3rd gear taking it up over 70mph and keeping it in 3rd the temp would climb about 5 degrees, but that was only when it was really hot. Really hot for me is 90+ degrees, any hotter then that and I would not even drive the car as it would be TOO hot with the top down.

I also had the same coolant in the car for over 5 years- Peak Global Extended life coolant.

When you drill the housing watch it if your up by the thermostat as the sender could interfere with the thermostat opening. Mine was in the way, I spaced it out and only drove the car once since then but temps did drop 5 degrees from that.
Hopefully your sender is not that long that its a problem- my autometer mechanical sender was a little large.

if you got a aluminum adaptor with the gauge like autometer sells you can have that welded right on the housing, gives you good solid threads without having to drill and tap.

 

Uhm make the 928.

 

I use maxima dual calsonic fans, the shroud fills the whole engine bay (with some trimming and no battery) and it uses two settings, I rarely need high but its nice to know that I have a high and low setting.

 

Ouch! I sliced my right index and my left ring just handling the mark8 fan. Those blades are sharp!

You the digitalsolo from the V8 board?

 

Ive been using the Fiero efan for awile with 0 Problems so ya ide say its pretty good!! Fits the Rx7 Stock radiator damn near perfect also...

 

Mark, those number are bogus numbers...they have been repeated, stretched and graphically tracked, but they are frankly just made up out of thin air.

And Rogrx7, my fan is not new, the donor car had over 100,000 miles.

Here it is in an earlier post in this thread, pics are included:
https://www.rx7club.com/showpost.php...3&postcount=28

I tested out two different Mark8 fans this weekend on the Porsche project. They tested at ~25-30 amps and they are only one speed. The later model Mark8's used a PWM fan control and had a one speed fan. So the feared Mark8 fan in reality pulls little to no more current than the Taurus fan.

 

I love it when people actually TEST things and post FACTS rather than spewing the **** that thier pre-pubescent brains conjur up.

Please, keep up the great work Jack. Your threads are always refreshing

 

Great post still being so many months later. But i hvae a question. If im not running A/C then do i need to run power for high speed or do i still need both?

 

If I lived in Philly, I would use low speed and be done with it.

 

I have not found high speed to be needed in Denver with no AC.
In fact, the past 6 weeks or so, my fan hasn't been on at all.

 

So how would i wire my fan without worrying about high speed for A/C?