LT5 Cooling and Radiators

[Dynomite]

What does that mean "no need to heat up the tires"?
What I want to see is actual Coolant Temperatures idling for 10 minutes with AC Full ON.....

Push and hold two buttons each side of Fan Speed Control until you get -00......
then push right Fan Button until you get to - 16.....
then push Fan Speed Control Button......
Show me the actually coolant temperature with Fans Full On (10) idling for 10 minutes in 100 deg F or greater deg F......
That would be interesting in 123 deg F ambient with Spal Fans and Dewitt Radiator

Do It......I Dare You

I did it yesterday in 100 deg F on Black Pavement in the sun.....idling for 15 minutes after a 20 mile cruise in both a 1990 and 1991 ZR1.
Got coolant temperature of 213 deg F stabilized after 15 minutes idling with AC FUll On (fans at speed 10). This with Ron Davis Radiator and Stock Fans with Haibeck Chip.
That is hard to beat

Originally Posted by GOLDCYLON

And 123 yesterday. But the proof is in the pudding. No need to heat up the tires boyz.

[GOLDCYLON]

Originally Posted by Dynomite

What does that mean "no need to heat up the tires"?
What I want to see is actual Coolant Temperatures idling for 10 minutes with AC Full ON.....

Push and hold two buttons each side of Fan Speed Control until you get 00:00......
then push right Fan Button until you get to 16.....
then push Fan Speed Control Button......
Show me the actually coolant temperature with Fans Full On (10) idling for 10 minutes......
That would be interesting in 123 deg F ambient with Spal Fans and Dewitt Radiator

Do It......I Dare You

Car would prob melt like the tires lol. Keep in mind that outside temp is nebulus as the sensor is just below the radiator but it is a TRUE indication of the heat coming up (radiating) from the Freeway tarmac in Phoenix. The acutal temp is really 116. However that is the heat our bottom air feeding Zs are truely subjected too. The hotest I ever saw that outside sensor reading is 131. Also why GM had a proving grounds out here

[RussMcB]

Originally Posted by Billy Mild

Anyone using water wetter?

Yes, especially in race cars. Not only does it assist in heat transfer, it has some additives that help the cooling system. The additives are often in anti-freeze, but most racing organizations don't want slippery anti-freeze on race tracks.

I've never heard a negative thing said about Water Wetter.

Valvoline Super Coolant (made by Zerex) is another similar product with a good reputation.

[Dynomite]

Originally Posted by GOLDCYLON

Car would prob melt like the tires lol. Keep in mind that outside temp is nebulus as the sensor is just below the radiator but it is a TRUE indication of the heat coming up (radiating) from the Freeway tarmac in Phoenix. The acutal temp is really 116. However that is the heat our bottom air feeding Zs are truely subjected too. The hotest I ever saw that outside sensor reading is 131. Also why GM had a proving grounds out here

SO.......I would really like to see you idle for 15 minutes after a 20 mile cruise (engine at full temperatures) with AC Full On and a digital Readout of Coolant Temperature........

Or.....better yet....

to compare you Spal and Dewitt set up to my Ron Davis Set Up....catch the temperature at just above 100 deg F in the evening and run that test idling for 15 minutes.......I got 101 deg C on the Digital Readout.

[Hib Halverson]

Originally Posted by Dynomite

Hib Halverson for one uses Red Line water wetter........

Use of Red Line Water Wetter

These days, I use either of two coolant additives, either Gibbs Driven CSP or Red Line Water Wetter.

At one time, I advocated solely Red Line's product but Red Line Oil has been sold twice–first, in 8/13, to Spectrum Corporation which was part of Dominus Capital's holdings and, then, secondly, in 6/14 when Dominus Capital sold Spectrum to Conoco/Phillips.

Since these sales, Red Line has already altered the formulation of Complete Fuel System Cleaner. It once treated 120 gallons of gas. Now it treats only 20 gallons, but the price is unchanged. Clearly, this is a move by Red Line's current management to increase profit on that product and do it in a way which customers will not realize unless they read the small print on the container. The reason I'm testing Driven CSP is in case Red Line decides to dilute the formulation of Water Wetter.

In fact, CSP may be a better product than the current Water Wetter because, while RLWW and CSP have a similar effect on cooling systems, CSP's formulation is said by Joe Gibbs Racing to more tolerant of hard water than the "leading brand" which, right now, is Red Line Water Wetter. That feature of the CSP formulation makes more tolerant of mixing with tap water in places where water has a high mineral content.

My current coolant mix in my LT5 is 100% distilled water with 1.5 bottles of RLWW. The next time I change the coolant, I'm going to swtich to 100% tap water and a bottle of Gibbs CSP.

As for the rest of my '95'd cooling configuration, I am still using the same Fluidyne radiator I installed in 1998 during the period of time that the late Jim Van Dorn and I developed that radiator for Fluidyne. The nice thing about the Fluidyne is that it was truly a "drop-in" fit. You simply removed the stock radiator and put the Fludyne in its place. No other changes were required. The Fluidyne's tube count and configuration along with the way the radiator was manufactured offered a noticable improvement in cooling performance. Unfortunatley, the Fluidyne radiator for late C4s was not a market success and is no longer made, but it proved to be a very durable product, having lasted 17 years in service in my 1995.

I also have a 170° thermostat, a calibration with revised fan-on strategy and a front air dam which is in good condition. Periodically, I pull off the top of the cooling stack to clean out any trash between the hvac, the oil cooler and the radiator.

As some may know, Jim Van Dorn died unexpectedly on 14 May at age 59.
In a strange irony, tomorrow (20 June 2015) Jim's three children are having a celebration of their Dad's life. They are holding this event in the Palm Desert, California area where Jim once lived.

The Van Dorn kids have asked me to come speak at this memorial. To honor Jim's memory, I'm going to drive Barney, my '95, on the five hour trip from where I live in Goleta to Indio where the celebration will be held.

The weather down there this weekend will be unseasonably hot–even for summertime in the California low desert. The high temperature on Saturday will be 115°F. That will be a great test of radiator that Jim and I developed 17 years ago and the cooling system configuration I've used all these years.

[Karl]

I will add my cooling experiences. Hopefully you don't mind.

I run Pete's under drive lightweight aluminum water pump pulley and so far with the Fluidyne radiator the cooling is under control.

A couple of weeks ago I was driving about 85 on a hot humid day, somewhere in the lower 90's and the coolant temp on the highway got up to ~208 and when I got off the highway it came down to ~200 and held there.

Today I sat in traffic and its ~81 degrees and humid and the temp did not exceed 200 until traffic began to move ~65 mph and it crept up to ~205.

*edit* Both above are with the a/c on full blast.

I am running distilled water and green antifreeze. Somewhere 60/40 distilled water/antifreeze.

[Dynomite]

Originally Posted by Karl

I will add my cooling experiences. Hopefully you don't mind. The more input/examples the better....and thanks

I run Pete's under drive lightweight aluminum water pump pulley and so far with the Fluidyne radiator the cooling is under control.

A couple of weeks ago I was driving about 85 on a hot humid day, somewhere in the lower 90's and the coolant temp on the highway got up to ~208 and when I got off the highway it came down to ~200 and held there.

Today I sat in traffic and its ~81 degrees and humid and the temp did not exceed 200 until traffic began to move ~65 mph and it crept up to ~205.

*edit* Both above are with the a/c on full blast.

I am running distilled water and green antifreeze. Somewhere 60/40 distilled water/antifreeze.

Here in Central Valley CA early afternoon in foot hills it was 105 deg F. With a Ron Davis cruising at a mild 55 mph with AC Full ON the Coolant temperatures were around 200 deg F. The Fans come ON at 205 deg F and OFF at 200 deg F.
Basically the Coolant Temperatures stayed in the range of Fan Operation.

[rkreigh]

I run the ron davis in the lpe and find that the factory fans aren't strong enough for the thicker cooling stack

I'm going to clean my rad out, marc serviced it a few years back and the old gal his 93k on it with the last 8 hours of driving up and down 211 in the mountains skyline drive and the back roads around the mountains keep you off 81 south and the drive is treat

I'd love to do skyline drive down to the dragon camping along the way

it would be a hoot.

[Dynomite]

Originally Posted by rkreigh

I run the ron davis in the lpe and find that the factory fans aren't strong enough for the thicker cooling stack

I'm going to clean my rad out

My experience is a bit different regarding 1990 Stock/Factory Cooling Fans and A Ron Davis Radiator........

I checked my fans, the fans blew a lot of air (like holding your hand out the window at 20-30 mph) when they came on pulling that air through the stack (AC Condenser, Oil Cooler, Ron Davis Radiator). The Fans came on intermittently almost immediately after starting the engine (with AC Full ON and AC Fan Speed 10). The Stack consists of the AC Condenser in front of the Oil Cooler and the Ron Davis Radiator the last in the stack (to the rear). I will check the Coolant Fans Air Flow through the Stack consisting of the Ron Davis Radiator. If I can measure the Air Flow even approximately one can use that Air Flow Rate to determine the condition of a Stock Radiator in Comparison regarding trash that might be restricting Air Flow. Or compare a Ron Davis to a Fluidyne to a Dewitts to a Cleaned Stock Radiator in regards to restrictiveness of Air Flow.

I will probably use the credit card swing test comparing the Stock Cooling Fans Air Flow to the Air Flow at various speeds out the window.......it is a start a step better than me just telling you what the Air Flow Feels Like

Or this Anemometer Ebay Anemometer

How much air or how restrictive the Ron Davis Radiator?......all I can say is the Fans blew air at what seemed to be the same rate as before
I installed the Ron Davis Radiator (actually a bit more air since that stock radiator was not as clean as I thought it was).

Also checked the bottom of the AC Condenser and Bottom of the Oil Cooler. The bottom of the AC Condenser which is most restrictive to air flow has approximately a clear 1 inch space to the bottom of the Radiator Housing. The air space between the Oil Cooler and bottom of the housing is approximately 1/2 inch.

Air can enter the 1 inch gap (or a bit greater) between the Oil Cooler and Ron Davis Radiators coming under the Condenser and Oil Cooler or up between the Condenser and Oil Cooler (approximately 1/2 inch gap) and through the Oil Cooler, or up between the Oil Cooler and Ron Davis Radiator (approximately 1 inch gap).....then up and through the Ron Davis Radiator.

The AC Condenser and Oil Cooler have a rather narrow gap between them (estimate 1/2 inch).

Originally Posted by Karl

I run Pete's under drive lightweight aluminum water pump pulley and so far with the Fluidyne radiator the cooling is under control.

I have a Fluidyne Radiator in 1990 #3032 and Ron Davis Radiators in the other ZR1s.

[-=Jeff=-]

So I am reading of the main benefits of the swap.. what are the downsides of a bigger radiator (excluding: fit, non-stock/vs stock)

Basically, in a perfect scenario, I pull the OEM swap in (brand x)*.. get it burped etc..

what are the negatives?

Brand x could be anything, Ron Davis, Champion, DeWitts, Fluidyne What ever