Heat torture cooling system test... Exploder mech vrs Tauras electric fans...

[sykanr0ng]

I was noodling on the idea of the multiple pass radiator and came across this tech tip some time ago on the Stewart Components website:

http://stewartcomponents.com/index.php?route=information/information&information_id=13

The vast increase in pressure required for the double/triple pass units seems to negate any of their benefits, although I'm not sure if most of the EB vendor units are the 'old style' or 'new style' radiators they differentiate between in the article.

Todd Z.

I would suspect the copper/brass would be the old style and the aluminum would be the new style.

 

[nvrstuk]

Good article...I've been reading/saying similar stuff like thisafter researching but it's hard to find more than a few well researched articles out there...thanks for posting up Todd!! Keep learning more and more on the in's and out's of cooling--with a long way to go!

Lot of myths out there!!

 

[chuck]

Todd, do you suppose that 1/3 of the radiator tubes would make more resistance to water flow than a t-stat does? I was thinking the t-stat would be the bottle neck but might be wrong. I wonder if they used a t-stat in their tests or did they do the whole thing on paper. 64x I am not sure about either, is that a measurement or a calculation. Also I am not sure what that means, if 16x doubles the pressure does that mean that 64x is x4?

 

[ntsqd]

The t-stat is supposed to be a restrictor. Either a t-stat or a restricting orifice of some sort is required to build block pressure, which is necessary to keep from boiling the coolant at localized hot spots.

When we had the BMW 2.0L in the '67 Elva Sports Racer rebuilt by IRL engine builder (remember that series?) Steve Jennings he recommended that we shape the restrictor like a carb venturi, and make the ID about 5/8" to start with. He must have known something or other. That engine never got hot and from ~122c.i. it made over 175 HP at the rear wheels with carbs, in a 1200 lbs car! (We don't know the actual peak because we couldn't load the tires hard enough to keep them from slipping on the chassis dyno.)

 

[chuck]

That is what I thought also, the Stuart article was a little confusing to me because they were not giving the parameters for the tests or if they were test or just calculations.
PS our baja racer would get down to 135 while racing at night but 180 during the day with a 180 t-stat.

 

[nvrstuk]

Chuck, that sounds like my old 351w...never could get to t-stat temp unless the entire radiator was covered with cardboard (depressed against it) OR I was towing something heavy like my old boat or travel trailer on the freeway! 7mo/yr it had the radiator totally covered...

 

[chuck]

We tried the cardboard but it would either fall out or we had to stop during the race and get out to remove it.
We ended up putting a large radiator in the back and had 2 large fans on a t-stat. That worked out for a while until the fans locked up blowing 60 amp fuses and melting some wire causing the engine to over heat and blow a head gasket. At mile 1247.
PS, it was a 69 351

 

[nvrstuk]

Sad news there...dang electric fans! At least when you lose a belt you usually lose other things too...then you have "system " failure instead of those ~¥|%+~¥€*!] dang electric fans!!

 

[ZOSO]

Glad to see this come up with some info. Im battling some heating issue on my 351w. current set-up is champion 3core with explorer serp and a sealed/shrouded taurus fan. It can idle all day long and run 200* on a 192 stat. once driving down the road it'll go 210-212 and stay there. Just took a trip across the state loaded down with camping gear and it ran up to 230 pulling the passes. I'd stop and 5 minutes of idling it would get back down to 200. wheeled for a few days and the taurus fan on high couldnt keep up when over 10-11kft(less air density). Then on the drive home I lost either the relay pack or temp switch. Hit 240 real quick. Pulled over and jumped the fan to high speed to get me home. The tstat failed open at that over heat point and stayed nice and cool the whole drive home never getting over 206* would cool off to the low 180's on the down hill stretch.

So Im going to start with a new stat. Looking into the robert shaw stat from WH. anyone use one? then going to go with the explorer mech fan and ditch the taurus fan.

 

[nvrstuk]

I've never posted this since it was irrevelant to the results of the test but the stock Tauras relay melted on my Torture test that day... it wasn't due to improper connections or wire gauge size it just fried possibly because the fan was on high the entire time...or the age all the components added to the resistance in line.

Anyway thought I would mention that it happened to me also .

 

[ntsqd]

I'm sure that there are occasions where the high flow t-stat's are the correct answer, but it's going to take a lot of convincing for me to stray from a standard t-stat.

For it to be high flow it has to be less restriction. If it is less restriction then the block pressure will be lower at all times. Which means that boiling of the coolant at hot spots is more likely to happen. I'd rather have the block pressure.

 

[DirtDonk]

That's a good point, but one I'm not sure is right or wrong. Never thought about it, but will see if anyone else has and figured it out. My impression was that the high-flow wasn't just about total volume of the opening, but shape and "quality" of flow with it's different shape. Sort of increases flow without losing too much pressure maybe? Maybe not...
Sort of like the difference between a Dyson and a Hoover.;D (Can't say that's true either of course, but it sounded funny in the moment%) )

I've used them for many years with great luck. However, since I've never really had an overheating issue to begin with, I can't say they "cured" what wasn't really there in the first place.
I do know that my coolant flows like gangbusters with my Flowkooler and Robertshaw/Johnson Controls thermostat. Unfortunately I all went old-school hot roddy on it and bought the 160° version thinking (at the time) that cooler was better.
Didn't have it cause any real issues, but never had a good heater after that either!

Have a 195° version I found somewhere waiting to go in.
But as ntsqd and others were basically saying, a good quality stock one should be sufficient for normal use too.
Of course, that begs the question, why does a company like STANT make so many different types for our engine? Is one "better" than another? Or does it just fit a certain set of conditions better than another?
I used to work closely with STANT and could never find anyone willing to sit down and talk tech about it. I'm sure that person existed, I just was never lucky enough to catch them.

I'm going to continue to use the full-flow versions as long as I can, because they work and I like the concept. But as I said, I can't say anything really bad about standard types either.

Paul

 

[chuzie]

I need to pressure test my system. I think my ron Davis is leaking and causing pressure drop thus inefficient cooling.

 

[toddz69]

I need to pressure test my system. I think my ron Davis is leaking and causing pressure drop thus inefficient cooling.

I'll be curious where it's leaking, if you indeed find a leak. I had two that leaked at the exact same spot!

Todd Z.

 

[ntsqd]

It all comes down to P = F*R (electrical types will recognize it as V= I*R) where pressure and flow are inter-dependent. If you reduce the resistance to flow you have to increase the flow to maintain the pressure. If you increase the resistance you have to decrease the flow to maintain the same pressure.

Resistance is resistance no matter what the shape of the orifice. What the shape of the orifice does change is the flow. That's not contradictory. If you have a flat plate with a 3/4" hole in it it will have a specific flow resistance. If you change from a flat plate to a venturi shaped orifice with the same 3/4" ID the resistance will be lower and it will flow more even though the opening is the same size. The flat plate does produce significantly more turbulence, which translates as cavitation.

In my case I'll be using an Explorer front dress, and I'll be using an OEM t-stat for that application. They're designed to work together and Ford put a lot of effort into the design of this cooling system. I've no desire to re-engineer it unless I have to. If I were to put a high flow t-stat in there then it's on me to find a pump that will increase the flow to offset the reduced resistance. Sometimes that is worth the trouble, other times it's just money spent for no overall gain. I see guys immediately modify a system without even testing whether or not the OEM system will work for them, and without prior knowledge that it won't. I don't understand this. I get the only wanting to buy parts once, but without detailed prior knowledge of that system and how it may or may not work in their application I think they're spending more than they needed to and setting themselves up for headaches in the process. You'd be amazed at how well a dead stock system can work if you let it.

 

[ZOSO]

Good info on the tstat. So next question is stay 192 or go 180? I never had heating issues until going explorer dress and efi with the taurus fan.

Also what fan and clutch is better? I have the factory metal explorer fan. is the plastic better?


For a relay set-up I was running a bmw 195/205 temp switch and a volvo 2speed relay pack. everything was brand new except the fan itself.

 

[chuzie]

I'll be curious where it's leaking, if you indeed find a leak. I had two that leaked at the exact same spot!

Todd Z.

Where the tubes meet the tank on the passenger side

 

[nvrstuk]

192 if EFI.

 

[ZOSO]

Well I pulled the taurus fan out today and installed the metal explorer clutch fan. Modded the factory shroud to cover the fan. I would say that at 900rpm idle the clutch fan flows more air than the taurus did on high speed any day. Now to get it out and test it in the heat.

 

[nvrstuk]

Well I pulled the taurus fan out today and installed the metal explorer clutch fan. Modded the factory shroud to cover the fan. I would say that at 900rpm idle the clutch fan flows more air than the taurus did on high speed any day. Now to get it out and test it in the heat.

Glad it's pulling so much air for ya! Should work great.