I've been giving this a lot of thought and the next nice day I'm gonna put my idea into motion First, I'm gonna remove and clean my radiator then add a transmission cooler. The next thing I'm gonna do is reverse my fan plugs (cut and splice if need be) because I figure that both fans run off the exact same part # relay, so there can't be any power difference. It would be (in my opinion) an advantage to having the BIG primary fan operating on my temp switch as opposed to it sitting idle and waiting for the ECM to kick-it on at 228. So it seems to me to be as simple as reversing the plugs as opposed to more complicated diagrams I have seen. I'll have the primary fan working as the secondary with the secondary working off the ECM with it's 228 "on" setting. I'm sure other people have done this, it seems too easy a positive "mod" to ignore.

 

Two thoughts, do you have a lower temp switch ?
Do you mind the fan running when the ECM would have turned it of at 40 MPH ?

 

If youre going to run that small one up front as your primary the car will overheat.

 

Before you go off on the deep-end, have you truly addressed the ~20 year components in your car?

Scale build up will kill the radiators ability to exchange heat......A worn water pump is not pumping the amount of fluid a new one would.....a Thermostat could be stuck....

Pulling the radiator and having it boiled out would be a good first step

 

...or burn a new chip with the fan "on" / "off" temps you want and the whole task takes 20 minutes.

Why do something the easy and correct way when you can turn it into rocket science and screw something up?

 

I have a 195 secondary fan switch and a 180 stat, how would the car overheat? Instead of the small fan working off the switch, the large primary fan will. As it stands now, my car rarely reaches over 220 and the primary has never needed to go on, I think the larger fan would be more efficient at keeping the car cooler than the small fan. I don't see this being anything complicated at all, as a matter of fact, I see it being something that SHOULD be done. I'd like to see my car run no hotter than 200 in traffic and I think I will achieve that with this simple "mod".

 

EWP

 

I hardly see 220 at the track...in the middle of a Texas summer!

I put a 4-core Ron Davis AL radiator in and got one for an automatic (in my 6-speed car).

I got a Canton sandwich adapter and ran -8 braided lines to the the radiator and use it as my oil cooler.

Now I don't overheat...ever. I think the worst I saw was 230 deg at TWS when it was mid-summer and 105 deg air temperatures...after 20 minutes of running it hard on track.

I agree with jhammons01...address the real problem.

 

I actually don't have any problems, I'm just looking for an easier way to properly cool the car. I'm simply changing fan designations, which I believe is how it should've been. If ever the car should reach 228 ( which I doubt it ever will) or when the A/C is put on, the smaller secondary fan will go on, without the ECM knowing the difference, while the larger (primary) fan will operate as the secondary off the 195 switch. No chip "mods" or any changes to the stock performance configuration, just a cooler car.

 

Make sure you carefully Consider electrical loads, wire size etc. If all looks good give it a whirl and report back the results.

 

because rocket science is fun!!!!

 

I think I found an easy solution to cooling a 2 fan set-up car that the "chip burners" don't want us to know and I can't wait to give everybody the results. Like I said earlier, both fans work from an exact relay and have the same gauge wire, which leads me to believe that they both fall within the same Hertz/Ohm/load/Amp perameters, because if they didn't, they would have different relays. Polarity should not be an issue because power and common should be the same and they may be reversable. Remember, the secondary pushes and the primary pulls.

 

Its not that simple...

these are ECM "controlled ground" or "power-grounded" circuits that the ECM uses other inputs to make the decision to activate or not. Electrical load goes far beyond the need of the relay that you can see and the effect of any additional loads (higher amperage) on the ECM can be damaging and unpredictable at best.

There is no real advantage to running the pusher fan on a street car anyway...its the last chance fan thats there to force some air flow against the condensor, NOT the radiator. Its neither shrouded for the radiator or ducted to direct flow to the radiator. It simulates a slight forward motion of the car to allow some fresh air to be sucked thru by the sucker or main fan that IS shrouded for max efficiency.

There are dozens of simple inexpensive ways to manage the sucker fan and still allow the ECM to operate as intended. Lower temp switches, programming, even manual ground path circuits that are after ECM input so they do not interfere with the ECM reference voltages.
Trying to re-engineer something that had millions of $$ of research is kinda a waste of time. These car were designed to run hot, and trying to get a ECM comtrolled car to live at temps under 200 and run right is a falacy. IT is tuned for these temps and that is where you probably should be focused on some changes...but they will ALL come at a price.

If the temps are not satisfactory at this time, you should consider upgrading the cooling system where REAL changes can be made that have no negetive effect on anything...like a bigger all aluminum radiator and a more efficient water pump. No downside to either of those upgrades and both will cost less than $350 together.

 

Your contradicting yourself, because you said "these cars have had $$millions$$ of dollars spent designing them to keep them running at a certain temp", now if thats true, wouldn't changing the radiator and waterpump achieve the same rusult? Only with the need for extra stuff (radiator, pump ect.). What I'm doing is the equivelant of putting a "Flex-a-lite" fan in place of a clutch-fan application, but I'm using an exsisting fan without changing the ECM's fan curcuit at all. Having the secondary fan acting as the primary makes more sense, because when the a/c turns on, it'll be the secondary that will blow right on the condensor coil. Based on my set-up, running a 180 stat with a 195 secondary switch, my car should maintain a temp between 180 and 200 tops, under any load condition. I'm an HVAC mechanic by trade and work for NYC and things like this are done all the time with positive results, a 1988 Corvette's computer controlled system is less complicated than an I-pod and if these cars are designed to run hot, then any "mods" to cool them would be counterproductive unless you re-designed the whole car to run cooler from the get-go, period. Remember, the fans both have a 2 wire power feed, common and positive, which means anything in the curcuit related to the ECM takes place before the fan and will then simply activate the fan on that curcuit. For arguments sake, I can wire-in a 12 volt TV to the secondary fan wires and when the car reaches temp, the TV will go on. The car won't cool, but I think it makes the point. Why spend extra money needlessly to cool the car when theres a BIG fan right there doing nothing.

 

For everyone reading this: The ECM will not know the difference between which fan is being operated on it's 228 degree/ A/C on curcuit, it's that simple. If anyone here is relying on the car reaching 228 to kick-on the primary fan, I think your car is running TOO HOT!! I, like most people, probably never have thier primary kick-on because our cars never reach that temp. So, why not utilize the cooling power of a large fan that otherwise goes unused you may ask? I'm going to, because it's already there I'm willing to bet anything that I'll reach my goal of temps no higher than 200 degrees without altering anything to do with ECM curcuitry, performance of the car or my wallet. If I have any problem, it might be the longevity of the primary fan because it's old and it will be running more often in this configuration.

 

I have a 96 LT1. I wasn't comfortable with the temps running in the 220's. I changed the thermostat to a 160, retuned with a hepertech and now my temps rarely run 200.

 

I was tempted to change the chip, I took out a superchip and put back the original prom then recalibrated everything. What else did the chip you used do? I'm just looking to run a little cooler without changing any of the stock peramiters. My trans dipstick gets so dam hot after an afternoon of cruising that you can't even touch it and thats only after reaching about 214 give or take. There is no way that temps in the 200's are healthy for any car. On the highway at 100 I'm at 175, I'd like to see temps between 195 and 200 in traffic at idle, no higher.

 

Your 1984 Corvette has normal operating temps.
Modern day EFI cars & trucks are designed to run between 205 to 220 degrees F coolant temps.
Engine is tuned to run most efficient there.

There is no real performance advantage to running coolant temps between 140 to 190 F in a stock engine, stock cammed, stock EFI TBI or TPI induction system running on pump gasoline.

Now if you switch over to a carburetor like a Rochestor Q- jet, or a Holley 4-barrel with a mix of race gas or aviation gasoline, the engine likely will favor lower engine coolant temps & with a hot aftermarket camshaft profile.
You can run more & a faster rate mechanical advance in a MSD, original HEI made from 1975 to 1979, or a Magneto afterwards without detonation taking place early on the gas hard.

Cheapest method to lower your coolant temps is to install a manual electric fan over ride switch under the dash or in the console.
Switch the fan on at will.
That front cooling fan on Z51 & Z52 cars is a joke. Near worthless.
And a POS.
Worry about the main underhood cooling fan.
Leaving the electric fan on constant takes power to run.
Watts or Amps of current.
Will shorten the life of your stock CS-130 alternator.
Working the full wave rectifier very hard at all times at low idle speeds.
And internal heat builds up fast with high current demands.
If there are any cheap POS china parts inside of your alternator, it will smoked dead withing 1 week.

 

I'd like to disect everything that you've written but it would take too long. I'll just say that you haven't read everything.

 

I did not change any chip. All I did was put in a 160 thermostat and retuned with a hypertech so the engine would know it had a 160 instead of a 180. This will automatically change your fan settings. Changing your fan settings is the way to run cooler. Just changing the thermostat will not do it. You have to tell the system it now has a 160 instead of a 180. I sat in line at a fast food place yesterday about 10 minutes with outside temps at 86 and it reached 200 even. Running, I was at 175 to 185.