Hi everyone. I am new to the forum and wanted to ask a simple question on cooling.

I know that putting a 160* stat in your car basically does nothing without re-programming the fans, etc. I also know that the stock radiator in my 94 LT1 is a single core.

I have found a good price on a radiator that is supposed to be triple core and have the same specs as the OEM radiator except core thickness. It claims to cool MUCH better than stock. (they all claim something)

Will putting this radiator into the vehicle make it run cooler or will I still have to replace the stat and reprog the fans??

I live near the beach and it gets SUPER hot here.

Thanks for any advice.

 

I'm a rookie C4 owner but I have found that if you are having issues with cooling in a C4 then there are a coupla things that should be checked. Oh, yes you do need to reprogram the PROM to call the fans on at a lower temp or you can wire up manual switches to call the fans when you desire.

You should also make sure that there is no debries in the rad. The C4 sucks everything from the bottom of the front valance so what ever is on the road is in your radiator. Only solution is to R & R the rad & clean out all the junk. Next make a screen to block the stuff. Go over to our ZR1NetRegistry.com site and look under "maintenance" and then select the "How to" tab the instructions are there to make a screen. Also make sure you are using the correct coolant, most C4's came with silicated coolant, GM spec 1825-M....that's what should be used if it's before 96(?)... don't mix DexCoolII in unless you flush out all the 1825-M 'cause the two don't mix. Ya gotta clean out the A/C condensor also as it will catch some junk too. Obviously the w/p must be good & the belt and the system should be flushed regularly...ya know good maintenance is important.

Then if you want to add the aftermarket bigger rad you will have one cold running C4. Are you having cooling issues now?

JMHO

Tom

 

Hi, Thanks for the response.

I am not having any issues right now, but the HOT weather is just around the corner and the temp gauge really stays up there when running around town. It gets and stays between 85-100 degrees here many months. Last year we had a few 115* heat index days.

I know that constant heat is HP robbing and also will break down the motor faster. I am looking to make the vehicle run cooler, noticably... and I don't really care about cost, but don't want to break the bank. I want to do it right with high quality parts that are pretty easy to install and wont cause other issues.

Also... the radiator is being sold by/at www.ExtremeRadiator.Com It is not fancy like the others but appears that it will do the job and the price is good.

thanks again.

macfos

 

Also, all maintenance is up to date. The vehicle had all new belts, hoses and fluids about 7K ago.

No debris either.... clean front, but we do live in a sandy area. Sand may be caught where I can't see it.

macfos

 

Maybe somebody on this forum who has a "DeWitt or a Be-Kool" (2 row aluminum)radiator can answer your question.Many people change stats and reprogram the fans but it would be interesting to see how many degrees cooler (if any) using the 2 row radiators the car will run using the stock 180 dg.stat and not reprograming the fans.

 

You're welcome!

Sand is the worst! The sand gets inbetween the fins and don't come out! I had very few leafs, candy wrappers & the like.....but I had a pile of sand after 4 hours of picking it out of the fins. That made my car run cooler but the key is getting the PROM reprogramed to call the fans on earlier and ofcourse keeping up on the maintenance.

Over at the ZR-1 registry we tend to lean to DeWitt &/or "BeCool" radiators as replacements. The ORR guys swear by those as our cars actually by pass the radiator completely at 5400 rpms, before that from 3000 rpms its a gradual progressive by pass, our w/p's flow too much for the std GM/C4 rads used in our cars...thanks GM!

What yr is your C4 because GM came out with updated fans that move more air....that's my next upgrade....and they do help low speed air flow in B to B traffic. That info is on our site also.


Tom

 

One thing you will need to do is become comfortable with higher coolant temps than older cars you have owned. 220 degrees is nothing to a car engine, completely not harmful. C4 fans come on at 228 F and the auxilliary fan comes on at 238 F. GM says in the owners manual to shut the engine off at 260 F and let it cool down. Even 260 F is not harmful to the engine and the reason GM says to let it cool down is because the coolant is withing 5 - 10 degrees of boiling with the normal 15 psi radiator cap and if the coolant boils it can go out the overflow and reduce the amount of coolant in the engine to the point where the heads have insufficient coolant in them and this can damage the heads.
In the hottest weather I have experienced, stopped at a long light, I have never seen my coolant temp exceed 220 F because I have a manual switch that I can turn my main fan on with. Even without the switch on, a test of my cooling system after an engine repair, with the engine idling the coolant temp rose to 228, fan came on, coolant dropped to 210 and the fan went off. My car cycled like this over and over. You don't have to do anything other than be sure there is no debris blocking air in the front of your radiator. I clean mine the lazy way, I shoot water backwards with my garden hose through the radiator.
GM engineers are not stupid, your Corvette without any additional help can keep the coolant temp easily within safe temperatures. You don't have to reprogram fans, install bigger radiators, change thermostats, or get out and wave a blanket at the front of your car. It isn't your vette that needs help, its your thinking. The multi row aftermarket radiators do reduce coolant temps and CFers have posted so.
Also, higher coolant temps increases HP and lowers engine cylinder wall wear, the exact opposite of your understanding!

 

thanks for the info tomtom... I will look into it. My Vette is a 94 C4 coupe. No extras or anything special. I have been restoring it for a few years and it is in excellent shape. I am replacing parts/systems one at a time with new parts or upgraded parts. The vehicle is 13 years old and I plan to keep it forever, so I am replacing every part little by little until I can get it as close as possible to "new". She's solid and will stay that way.

jfb... Do you have any info on good stock replacement radiators then?? Why are Lingenfelter and other Vette performance shops always talking about the horsepower robbing heat that comes from the vehicle? Am I mis-understanding the heat concept here? What you are saying is total opposite of my understanding and just want to figure out where the heat is coming from and how to cut it down a little.

thanks for the advice.

macfos

 

the Stock radiators can be had at any good radiator shop. If I ever have to replace mine, it will probably be a DeWitt which costs more than stock but has higher heat transfer and a double row of tubes and fits without any altering. I don't like soaring temps either even though I know I don't have a thing to worry about until the coolant reaches 260 and mine never has. I cannot explain others misunderstanding of engine performance, but one aspect is that air traveling through the intake gets warmed by the intake manifold being at the engine temp and hot air is less dense and reduces HP. But what is not taken into consideration by these people is the fact that hotter engines transfer fewer BTU's of heat from the combustion chamber (heat transfer is directly proportional to the difference temperature) and internal combustion engines are heat engines and if you take heat out of the combustion chamber, you also take horsepower from the combustion chamber. This is called thermal efficiency and it overrides the warming of the inlet air. Read Smokey Yanuck's last book, he says that stock cars run their engines at 240-260 F and make the most HP in that temperature range. You can also find via google from the oil companies, HP vs oil temp curves showing increasing HP with increasing oil temps. The limit is of course where lubricating oil begins to boil and then it has insufficient lubricating qualities and the engine bearings will be the first to fail. Sorry I cannot supply any links to these sites but they have been posted here in the past.

 

The Extreme radiator is a 3 row copper/brass unit and it will not perform as good as a single row aluminum radiator. It will also weigh about twice as much. A one inch tube in an aluminum radiator is equal to about three rows of 3/8 copper tubes. If you are not looking to upgrade to a double row aluminum, then I'd just stay with the stock radiator, which I think you can get for about the same price.

 

Thanks for the good info!

Also, since I know the facts on the ExtremeRadiator, where and what is a good aluminum replacement that is equal to factory in size.

I guess at this point I am now just looking for a new, better looking radiator and some weight reduction since the cooling is not an issue.

Thanks again.

macfos

 

I don't know about your '94 but my '96 had fans that came on automatically when you turned on the A/C and they ran all the time with the A/C on. I never saw the temp get higher than around 220 and I live on the Gulf Coast and used that car in many parades. I basically ran my A/C just about all the time as here on the Gulf Coast it is either hot or very humid requiring the defroster.


I agree with the previous poster who stressed keeping your radiator fins clean. At the time I owned the '96 I had just built my house and I had about 20 feet of dirt driveway before getting on my long paved drive. I developed the habit of turning off my A/C just prior to turning into my driveway and anytime I got on an unusually sandy area to avoid the "vacuum cleaning" fans from sucking up excess grit and dust into my radiator fins and engine bay.

I was amazed at how much cleaner the radiator and engine stayed after I started doing this!

 

Try www.absoluteradiator.com they might have a good stock one. I think modine makes a factory replacement for about $150ish.

 

Tom,
Will your radiator run a little cooler without changing the 180 stat and not reprograming fans on a stock 95 LT1?if so approx how many degrees
thanks

 

I've wondered if anyone has retro fit a pre 1992 oil cooler onto an LT1 car.

 

These things are like vacuum cleaners for the road
I found bird feathers in mine along with the regular burger wrappers etc.

 

I would expect to see no change at all. That's because the stock settings are desigined to keep it high. You need to "tell" it to run cooler or it just won't know any better. It's kind of like installing a huge engine and then not giving it any gas.

 

I don't know if this will help your situation, but I replaced both of the cooling fans on my 1990 Vert in the last 4 months, and it made a difference in the cooling. When I replaced the Primary Cooling Fan two weeks ago, I noticed that it turned quite a bit faster and smoother. The old one was 17 years old and probably lost some of it's guts. It was also making some noise when it turned on & off. But my car has run considerably cooler and I feel more confident in it's reliability now. The fans were $77.00 each at my local dealership (they give me a small discount - I think they retailed for $99) and you're looking at 1 1/2 - 2 hours Max. Just a hint: unbolt the radiator and pull the whole primary fan housing out from the top.

 

That’s real interesting, I’m on a dirt road also and never really had that thought about shutting A/C off. However on my 94, when you shut off the A/C, there is a time delay before the fan shuts down (of course temp under 228). If I want the fan off right away, I would have to shut down engine and re-start with A/C off. Never measured the time delay and don’t know if the 96 works the same.

If it is real dusty when I stop for the mail, I shut down and wait for the dirt to settle before I even get out.