Fluidyne radiator question

[secondchance]

For those who are running Fluidyne radiators - are they single row or dual row?

Thanks.

[XfireZ51]

For those who are running Fluidyne radiators - are they single row or dual row?

Thanks.

Just installed one. Don't know but it fits under the stock shroud.

[secondchance]

Just installed one. Don't know but it fits under the stock shroud.

That's why I am looking at either Fluidyne or Dewitt. Both will fit under the stock shroud w/o modification.
Just trying to determine which will cool more efficiently.

[XfireZ51]

That's why I am looking at either Fluidyne or Dewitt. Both will fit under the stock shroud w/o modification.
Just trying to determine which will cool more efficiently.

I actually increased the temps for fans ON just to keep motor at an operating temperature of 85-90C or 180-190F.

[secondchance]

I actually increased the temps for fans ON just to keep motor at an operating temperature of 85-90C or 180-190F.

What kind of outside temp? Mid 80s?

[PhillipsLT5]

Fluidyne works well for me in AZ, 1/4 mile, track days, 1 & 1.5 mile all good

[XfireZ51]

What kind of outside temp? Mid 80s?

Those are coolant temps and Celsius. It's cruising at about 85 C which is just fine.

[XfireZ51]

What kind of outside temp? Mid 80s?

Sorry misunderstood your question. It was right about 80F outside.

[secondchance]

Sorry misunderstood your question. It was right about 80F outside.

How is it in a hot day, stop and go traffic with AC on?

[XfireZ51]

How is it in a hot day, stop and go traffic with AC on?

I had just gotten my AC recharged. Driving w AC on and cruising at 65, coolant temps stayed at 85C. It would increase to 90C as things slowed down. Haven't done stop and go. I have my fans coming on at about those points.

[XfireZ51]

My purpose is just to report my observations since I just did an install of the Fluidyne. Not here advocating that people should install one. As I continue to drive in varying conditions, I will be checking performance in a number of conditions and make my results public here. Today's ambient temps will be low
90's so I'll be checking performance out in those temps. I don't like being surprised, but rather want to know what the limits are.

[GOLDCYLON]

I am running a Dewitts with dual spal fans. so far in Arizona I am happy with it.

My toughts on the project.

http://www.zr1.net/forum/showthread.php?t=20756&highlight=dewitts

[GOLDCYLON]

OK......what does that mean exactly?

Tell us what your Coolant Temperatures are on a 100 deg F day while stop and go driving for 30 minutes.....Say traffic between stop lights and no speeds over say 25 mph and lets say AC On.....with AC Fan on #10.

About 130. On the freeway with ac on doing 70 Miles per hr about half band whatever temp that is.

keep in mind I drive in AZ Stop and go temps outside radiating from the roads and freeway are easliy 115 and up last summer in this conditions outside temp was 122.

[GOLDCYLON]

Say......... Dual Spal Fans :p I am assuming those Dual Spal fans are pulling a lot more air through the radiator and even at stop light your radiator thinks you are moving at 50 mph. :sign10:

You just introduced another variable of pavement temperature. Which most experience the pavement just like you :D

None of us experience Spal Fans like you ;)


Yes about 130 more FPM per fan than stock. The car hums like the newer car fans.

Just like the lady says at time mark .11

http://www.youtube.com/watch?v=xCIF6JF1O5U

[XfireZ51]

Here's latest observations driving with A/C ON, ambient temps are 90-94F.
Driving in Stop and Go for about 15 min. CTS got up to 108C/227F sitting at a light. Intake Air Temp got up to 36C/96F. Once I got rolling temps began dropping and at a steady 60-65mph cruise temps stabilized at about 87C or 188F.
Driving around in our suburban town, CTS ranged between 88-94C.
With a modded motor, you are putting in a lot more heat to get more power out. We know the A/C comp on these cars was already marginal from the factory.
Perhaps as Darryl has pointed out, more powerful fans may be the answer. Not sure the Fluidyne by itself is enough for Stop and Go, idling with loads of other traffic all around you. Without A/C, I think the Fluidyne does a good job at keeping temps reasonable. My $.02.

[secondchance]

Great discussion guys. Even with OEM radiator and 180 stat w/1/8" hole drilled on the flange, I have no issue at 55 mph plus speed. As is car maintains 192 - 200 degrees F. It's stop and go traffic in 90 plus days, w/ AC on, the coolant temp climbs to 230+.
Based on discussion above high efficiency radiator removes heat from the motor but the radiator needs good air flow (good fans) to shed heat. Makes perfect sense.
Since going to 380, I can tell the cooling system is not up to par. So, I think, a good radiator (I'm thinking Dewitt since I know they are two row and I can't confirm the same for the Fluidyne) topped off with a pair of Spal fans are in order.

Thanks all!

[XfireZ51]

My only concern regarding AC load is when Mrs. Xfire is in the car. She won't ride around in it unless there's air. For me, I use the windows and listen to the exhaust note.

[tf95ZR1]

That's why I am looking at either Fluidyne or Dewitt. Both will fit under the stock shroud w/o modification.


SC, you just built a 380 and don't want to trim a little plastic?
I placed a Ron Davis 3 row. I can look it up, but I think I had
to trim 3/4" here, 1/2" there. No big deal. Runs MUCH cooler.

[PhillipsLT5]

I do not think fluidyne makes these anymore, so maybe not a option, unless used

[secondchance]

I do not think fluidyne makes these anymore, so maybe not a option, unless used

I see Fluidyne FHP11-96cor for sale when googled. Also, on Ebay.

[GOLDCYLON]

Since going to 380, I can tell the cooling system is not up to par. So, I think, a good radiator (I'm thinking Dewitt since I know they are two row and I can't confirm the same for the Fluidyne) topped off with a pair of Spal fans are in order.

Thanks all!

Yep said the first 380 build member ;)

[GOLDCYLON]

Extra rows buy you extra time. due to extra capacity. I chased this problem down with my 67 camaro. Damn car always overheated with AC on.

End solution was 4 row radiator with a flex fan. Problems solved.

Factory radiator was a one row. WTF?

Replaced with a 2 row. Same problem

Replaced with a 2 Row and a 5 blade OEM fan GM solution was a 4 bladed fan. Same problem. WTF?

Replaced with a 3 row was more acceptable until the water pump shaft broke throwing fan into raditor. Serriously WTF

Had custom 4 Row built and added a balanced multiblade flex fan. Seriously the front end of the 67 camaro had a crap load of room for a bigger radiator!!!!

Never had a cooling problem again. Sometimes you have to out enginner the engineer.

How does this translate to ZR-1s ? easy. The principals the same... increase the rows or core capacity and increase the fans cfms. Solves cooling issues on modded and non modded ZR-1s.

[chriskinzel]

Dumb question here. Are these Spal fans added in front to push more are through, or replacing factory fans behind radiator as sucking more air through?:neutral:

Chris

[GOLDCYLON]

Dumb question here. Are these Spal fans added in front to push more are through, or replacing factory fans behind radiator as sucking more air through?:neutral:

Chris


Behind.. They replace the original fans and fan support stucture. As stated in the youtube video. Its certainly sucking lol

http://www.dewitts.com/collections/spal-fans/products/11-spal-dual-fans-only

http://cdn.shopify.com/s/files/1/0164/0230/products/spal_dual_fan_sp846_medium.jpg?v=1342720938


specs

Height(IN): 16.26

Depth(IN): 4.25

Width(IN): 23.46

Airflow(CFM): 2780

[PhillipsLT5]

I see Fluidyne FHP11-96cor for sale when googled. Also, on Ebay.

Good to know, happy with mine

[PhillipsLT5]

Extra rows buy you extra time. due to extra capacity. I chased this problem down with my 67 camaro. Damn car always overheated with AC on.

End solution was 4 row radiator with a flex fan. Problems solved.

Factory radiator was a one row. WTF?

Replaced with a 2 row. Same problem

Replaced with a 2 Row and a 5 blade OEM fan GM solution was a 4 bladed fan. Same problem. WTF?

Replaced with a 3 row was more acceptable until the water pump shaft broke throwing fan into raditor. Serriously WTF

Had custom 4 Row built and added a balanced multiblade flex fan. Seriously the front end of the 67 camaro had a crap load of room for a bigger radiator!!!!

Never had a cooling problem again. Sometimes you have to out enginner the engineer.

How does this translate to ZR-1s ? easy. The principals the same... increase the rows or core capacity and increase the fans cfms. Solves cooling issues on modded and non modded ZR-1s.

Radiator hell

[GOLDCYLON]

Are the spal fans a direct fit?
If not.......what is the fitting?

Can one remove existing fans and drop in these spal fans?

Are the electrical connections plug and play or modified?

What is the source and model number for these spal fans?

NO they come as a unit as pictured you actually gain more room in the front of the motor by doing this mod

Plug and play

No idea and I doubt Dewitt's product number will be the same and these are an improvement over Dewitt's earlier models which was a generic bracing system that you had to adapt to fit the radiator with no directions. Those were the fans I returned in 2008

[GOLDCYLON]

Radiator hell

Yep I wasn't in a good place for a long while

[5ABI VT]

Read a lot about radiators over the years. in my 93 ltx car.. Mezziere HD waterpump. stock original rad. no problems whatsoever keeping the car under 205/210. 1100 idle. Don't want to open a new can of worms here but I believe the flow of a stock pump at idle is just too slow through the system and many people blame a radiator.

[A26B]

Read a lot about radiators over the years. in my 93 ltx car.. Mezziere HD waterpump. stock original rad. no problems whatsoever keeping the car under 205/210. 1100 idle. Don't want to open a new can of worms here but I believe the flow of a stock pump at idle is just too slow through the system and many people blame a radiator.

Do you think maybe July temps in Toronto Lo58 to Hi78F, hottest month of the year might have something to do with that? Especially compared to Phoenix, AZ.

It could be low water flow at idle, but the LT5 is well known for its high flow water pump, hence the coolant bypass valve.

For optimum performance, coolant flow has to be balanced with (1)flow rate capacity, (2)thermal exchange capacity of the radiator, i.e. coolant flow capacity, (3) surface area, (4)exchange media (air flow) volume AND (5) ambient air temperature.

Since we don't live in a steady-state climate, the components have to cover a variable range of conditions.

Looks like Dynomite was typing at the same time and we share some of the same sentiments.

[A26B]

Excellent point of discussion :thumbsup:

.........It seems to me.......(I am having a difficult time finding the LT5 Water Pump Flow characteristics) that all I would have to do to test your theory is rev the engine up at a stop light. I will test that out today and report back :handshak:

When I installed my Ron Davis Radiator, I contacted them for empirical capacity of the radiator. They could provide thermal exchange plots, but had never tested the radiator for coolant flow capacity in terms of gpm, to see just how much the radiator could flow in a mock cooling system, before inlet pressure exceeded the working pressure of the radiator.

I am interested in this factor, suspecting that the LT5 coolant bypass system may not be necessary with the Ron Davis radiator and that the thermostat, in stock configuration may be the limiting factor in total radiator flow capacity.

[5ABI VT]

Our temps do vary this year being very cool so far but it snot uncommon to get over 90 during june-august. I will admit however most times I drove the car it was late at night from 1-5 am. Finding clear spaces for 4th gear datalogs to 8000 rpm weren't exactly easy during the day;)

I am not familiar with the coolant system on the LT5 ill need to read up on that bypass valve. I also wanted to look into an electric setup. Does anyone offer one? Im a big fan of it having tried a normal mezziere then an HD on the ltx build. Waterpumps do have to try and do it all and I believe that's quite a compromise. At low rpm the engine is generating the least amount of heat while at max rpm the pump can cavitate and its generating much more heat. I believe the high rpm would be a priority for engineers for obvious reasons. I used to cruise in 2nd or 3rd at high rpms and oil temps were always a concern in my car but the coolant was always rock steady.

I had ideas of using the gen 7 n20 controllers in the ecm to setup the mezziere to spin slower below 3500 and get more juice above that. ideas ideas :blahblah:

[Hog]

[QUOTE=A26B;208147]Do you think maybe July temps in Toronto Lo58 to Hi78F, hottest month of the year might have something to do with that? Especially compared to Phoenix, AZ.

[QUOTE]
Average high temps temps are 26°C/78°F for Toronto and 41ºC/106ºF for Arizona.
Factor in the humidex and up here is can feel just as hot as Arizona. AT least in ARizona your sweat can evaporate. Up here it cant with all the humidity.
This year though, it has been a VERY cool Summer, with only 1 single day at 30ºC and above.
Phoenix only gets 1 day per year below the freezing point.

That being said, I dont think humidity affects car cooling like it affects human beings cooling as the car doesnt use evaporative cooling while humans do. So the less cooling capacity should be required in Toronto vs Phoenix.

Also, there is more to cooling than core number. A single core rad can cool better than a 2 core rad. It all depends on the design/construction.

[GOLDCYLON]

It was 115 yesterday. Car Displayed 123 outside and it cooled down to 119 on the 101 freeway after leaving I-17 so much for averages Eh lol ?

More rows in your radiator buy you time as its a function of greater capacity only.

When I had my 4 row built the rad shop gave me a simplistic example. You take a one row he called it for argument's sake a glass of water on a hotplate vs a gallon of water on the same hot plate or a 4 row. You are buying time until the car can start moving again and cool down.

[WVZR-1]

I will test that out next few days and report back :handshak:

Oh...and I will run that experiment with a Ron Davis Radiator as well as Stock Radiator at 100 deg ambient temperatures (Exactly 100 deg F here Fri through next Thur so plenty time to run experiments)



I would think that to compare the radiator effectiveness all one would need to do is at a consistent RPM and at operating temperature just do a temperature check of temperature "IN" at the radiator and "OUT" at the radiator with an IR Handheld. It would be very easy to do this with "fan ON" and "fan OFF" also.

[WVZR-1]

The discussion I thought was radiator efficiency but maybe I overlooked something, now your claiming that you can do comparable testing using different cars with different CTS sensors, dash senders and such. Bypassed cooling modifications etc included.

The radiator doesn't care about all of that, it's in and then out! If the radiator is compared at the same comparable RPM with engine at operating temperature (which the IN we would assume to be comparable) then the OUT is the results. There's nothing I believe that could dispute the efficiency. Now if the IN is not comparable then you've only determined there's a cooling system situation maybe with one or the other cars NOT the radiator.

The efficiency of the radiator is the result of construction, the fact that it's more or multiple rows of tubes is not the defining performance advantage. If a radiator has multiple tubes but has no provisions in the tubes to control the flow then it's likely NOT giving the cooling fins the time required to transfer the heat to air.

Does moving air effect efficiency? Certainly, but if one radiator is more efficient at a dead stop (RED LIGHT) then it could be maybe "wrongfully" assumed that it might be more efficient with the moving air.

Do your "road test" then bring them all to a stop on any surface of your choosing and then give them the IR hand held test with AC still maxed.

[Blue Flame Restorations]

Everyone, this forum is a place to exchange, learn and enjoy the ZR-1 and the Brotherhood.

Time to relax and enjoy.

[WVZR-1]

Everyone, this forum is a place to exchange, learn and enjoy the ZR-1 and the Brotherhood.

Time to relax and enjoy.

I don't have a problem with any of that Brett but a post that I had commented on I guess was "deleted" by Cliff, my remark was directly to the post that he's since deleted. I was "relaxed" and was "enjoying" - I was also exchanging and learning!

[GOLDCYLON]

Everyone, this forum is a place to exchange, learn and enjoy the ZR-1 and the Brotherhood.

Time to relax and enjoy.

X2 I think you "enjoy" it too much WVZR1. Share ideas only

[Blue Flame Restorations]

Dave, you have a lot of good information and I enjoy reading your posts, except where the !!!!! is used out of context. I believe that causes others to mis-read your information in the manner you may intend.

Not everyone will agree. That's ok. We all need to keep things civil and we may just learn something as part of the healthy discussion.

[Dynomite]

The Bottom Line Question for any discussion regarding Effectiveness of LT5 Radiators/Cooling Fan Systems is How do the Radiator/Fans Cool the LT5 Engine with AC On at 100 deg F Ambient Temperatures while idling in traffic.

Using HVAC Display for Engine Coolant Temperature (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp.html#post1580070560)

Let us assume for simplicity that LT5 engine cooling is about the Radiator Air Flow and Radiator Coolant flow (as 5ABI VT and Goldcylon suggests). Lets further assume that the engine sensors, heat generation, spark advance, compression, load are identical between engines at a certain engine speed and ZR-1 speed in other words nothing to consider other than the air flow, coolant flow, and coolant temperature from the HVAC Display (AC ON and AC OFF).

I am going to do some testing to verify exactly how two ZR-1s here in CA (90' with stock radiator and 91' with Ron Davis radiator) behave at 100 deg ambient temperatures (stop and go and on freeway at various speeds). I will determine exactly what the coolant temperatures are at 60 mph and 2,000 engine rpm in 5th Gear (including the worst condition idling with ZR-1 not moving). The Conditions I have are a 180 deg F Thermostat and Fans ON at 205 deg F and OFF at 200 deg F running on 91 Octane Fuel (Marc Haibeck Chip).

Since this discussion was about Fluidyne Radiators, it would be interesting to see how the Fluidyne Radiators Cool the LT5 under the same conditions of 100 deg F Ambient Temperatures. That would then say something about the Stock Radiator, Ron Davis Radiator and Fluidyne Radiator effectiveness in cooling the LT5.

I am thinking ALL radiators function well at ambient temperatures around 90 deg F and lower.....it is the 100 deg F ambient temperatures that are of issue.

Using HVAC Display for Engine Coolant Temperature (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp.html#post1580070560)
Water Pump, Coolant Temperatures, and Coolant (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp.html#post1580070561)
Coolant Characteristics (Mix, Pressure, Elevation) (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp.html#post1580070570)

A. Experiment Number 1
1990 Fans On 205 deg F Fans Off 200 deg F
Stock Radiator
100 deg F Ambient
at least 50% Coolant Mix

AC On 72 deg AC Fan 7
Cruise 60 mph 5th HVAC temp 220 deg F (after exceeding that temperature during the idle test)
(this was interesting because once the temperature came down to 204 deg F with AC Off the temperature did not rise above 205 deg F with AC On)
AC Off 60 mph 5th HVAC temp 204 deg F and dropping slowly
Fans are Controlling Coolant Temperatures when AC is Off

AC On 72 deg AC Fan 7
Idle (not moving) HVAC 235 deg F and climbing (idle for 5 minutes)
Coolant Temperature would keep climbing if I did not turn AC Off within a few minutes

AC Off
Idle (not moving) HVAC 230 deg F and dropping slowly
Coolant Temperature CAN BE CONTROLLED by Turning AC Off

B. Experiment Number 2
1990 Fans On 205 deg F Fans Off 200 deg F
Stock Radiator
90 deg F Ambient
at least 50% Coolant Mix

AC On 72 deg AC Fan 7
Cruise 60 mph 5th HVAC temp 205 deg F

AC On 72 deg AC Fan 7
Idle (not moving) HVAC 228 deg F (idle for 10 minutes)
Coolant Temperature is stable at 228 deg F with AC On with Ambient Temperature 90 deg F

In Summary From this experiment at 100 deg F and 90 deg F Ambient Temperatures the 1990 ZR-1 with stock radiator and Marc Haibeck Chip controlling the fans On at 205 deg F and Off at 200 deg F the following results were obtained.........

1. The Fan thermal switching control the Coolant Temperature (100 deg Ambient) when moving with AC Off (With AC On the Fans are always On).

2. At 100 deg Ambient Temperatures the 180 deg thermostat is not a player staying open under ALL conditions.

3. At 100 deg Ambient Temperatures the Coolant System FAILS when idling in traffic or at stop lights for over 5 minutes with AC On.

4. Excessive Coolant Temperature at Idle with AC On can easily be controlled by turning the AC Off.

5. It also was determined that if the Ambient Temperature dropped to 90 deg F the 1990 ZR-1 can idle in traffic at a stop indefinitely with AC On.

(For those not having the Marc Haibeck Chip the Fan Controlled Coolant Temperatures in this experiment would be 234 deg F).

Next the 1991 ZR-1 with Ron Davis Radiator ;)
C. Experiment Number 3
1990 Fans On 205 deg F Fans Off 200 deg F
Ron Davis Radiator
100 deg F Ambient
at least 50% Coolant Mix



B. Experiment Number 4
1990 Fans On 205 deg F Fans Off 200 deg F
Ron Davis Radiator
90 deg F Ambient
at least 50% Coolant Mix

Notes:

1. When testing Coolant Temperatures at Idle, then increasing the rpm, the Coolant Temperatures rose.
This indicates the higher Coolant Temperatures at Idle are probably not caused by low pump flow.
2. The Water Pump Flow at 800 rpm is 15 gpm. The Water Pump actually gets more efficient as the rpm increases from idle to 2,000 rpm.
As Per Marc Haibeck graph provided to the ZR-1 Net email list by Graham Behan about ten years ago, the water pump flow rate is:
15 gpm at 800 rpm
18 gpm at 1,000 rpm,
44 gpm at 2,000 rpm,
65 gpm at 3,000 rpm,
90 gpm at 4.000 rpm,
120 gpm at 5,000 rpm at which time cavitation is starting.
3. Marc pointed out "the high flow rate design of the water pump assured high volume of coolant through the cylinder heads to wash away boiling bubbles that lead to hot spots around the exhaust valves". Another reason blocking TB Coolant works so well as any remaining air in the coolant system gets washed back to the top of the Radiator and out the pressure relief .
4. The Dual Thermostat Bypass pressure is apparently 5 psi and block resistance at 100 gpm is approximately 20 psi. I am not sure what the radiator Head Loss is at various flow rates but definitely depends on the radiator type.
5. It would seem that the Coolant Pressure Relief Cap on top of the Coolant Expansion Tank in front of passenger side set at 15 psi would assure the radiator maximum pressure would be 15 psi plus the Bypass Pressure of 5 psi or 20 psi.

[Hog]

It was 115 yesterday. Car Displayed 123 outside and it cooled down to 119 on the 101 freeway after leaving I-17 so much for averages Eh lol ?

More rows in your radiator buy you time as its a function of greater capacity only.

When I had my 4 row built the rad shop gave me a simplistic example. You take a one row he called it for argument's sake a glass of water on a hotplate vs a gallon of water on the same hot plate or a 4 row. You are buying time until the car can start moving again and cool down.

Yes, the averages are out the window for both of our areas. Ive got a cousin up from Phoenix and she said it cools down to 80-90º at night. Geez, thats warm. Ive been sleeping with the winbdows open with nightly lows of 50ºF. Weird weather for sure.

SInce you have a built 4 core rad, I would love to see the results of some water mist spraying on your rad, esp with your dry climate. It would work great.

You are correct, the extra coolant capacity, thus the extra heat carrying capacity of your rad buys you time before you reach criticality. Kinda like wearing thick gloves vs. thin gloves. Once you grab a cherry hot piece of metal, you will get burned with either pair eventually, but the thicker gloves buy you time to shake them off.

Once the air enters your rad, it can only take on so much heat. If the 1st core saturates the air with heat, the last 3 cores do nothing in regards to shedding heat.
However if you can force more air through quickly enough, you will see some some advantage. The more air molecules you force through the rad, the more heat can be removed from the rad. Of course there are many variables at play.

The packaging of the C4 is challenging. Anyone played with heat extractors to help get the underhood heat out?

[Dynomite]

The packaging of the C4 is challenging. Anyone played with heat extractors to help get the underhood heat out?

Ya......after my experiment idling in 100 deg F .....with AC On and then AC Off....opening the hood did drop the temperature a couple degrees......With Headers I think it would be worse under the hood.

I have no clue how one would direct heat coming through the Oil Cooler, AC Condenser, and Radiator downward under the engine and somehow directing cool air above the engine except a new hood design with louvers.

The questions to be asked (specifically for those in the South West)......

1. How long can you sit at a stop light with AC On (AC Fans medium to high) when the outside air temperature is 100 deg F or higher?

2. Secondly, how high do you let your Coolant Temperature get under those conditions?

If you can sit indefinitely in 100 deg F Ambient Temperatures with the ZR-1 idling....what the hay do you have for radiator and fans? :D

Any one driving a ZR-1 around Phoenix, AZ the next ten days? :sign10:

[5ABI VT]

The problem I see with raising rpm is I think of the heat generated by the cyinders being absorbed into the coolant through the heads and block.. when you raise the rpm say from 1000 rpm to 1500 rpm.. that's 50% more compression cycles and more heat generated. I think the only way to truly compare pump flow.. would be to overdrive it or swap for an ewp .

My thoughts on heat extraction would be to do it like the c7. Angle the rad forward, make a plate directing flow through the rad straight upwards and have a cutout in the hood.

[GOLDCYLON]

Ya......after my experiment idling in 100 deg F .....with AC On and then AC Off....opening the hood did drop the temperature a couple degrees......With Headers I think it would be worse under the hood.

Cliff I would agree if the headers are not JET or SWAIN coated. Mine are and its amazing the difference in heat transfer. Jack your car up after stop. Wait 15 mins and grap the headers no problem. Grab any part of the engine during the same time period and waffle iron hot lol

I have no clue how one would direct heat coming through the Oil Cooler, AC Condenser, and Radiator downward under the engine and somehow directing cool air above the engine except a new hood design with louvers. YES other than hood louvers maybe on the sides and tops of the hood


The questions to be asked (specifically for those in the South West)......

1. How long can you sit at a stop light with AC On (AC Fans medium to high) when the outside air temperature is 100 deg F or higher? In my situtation till I run out of gas


2. Secondly, how high do you let your Coolant Temperature get under those conditions?

I dont get concerned until after 240

If you can sit indefinitely in 100 deg F Ambient Temperatures with the ZR-1 idling....what the hay do you have for radiator and fans? :D

Any one driving a ZR-1 around Phoenix, AZ the next ten days? :sign10:[/QUOTE]

[Dynomite]

Cliff I would agree if the headers are not JET or SWAIN coated. Mine are and its amazing the difference in heat transfer. Jack your car up after stop. Wait 15 mins and grap the headers no problem. Grab any part of the engine during the same time period and waffle iron hot lol
YES other than hood louvers maybe on the sides and tops of the hood

In my situtation till I run out of gas
I dont get concerned until after 240



My theory is simple regarding coating of the Headers......My Headers are NOT coated and are SOOOO HOT and all that heat goes into the Engine Compartment. Your Headers push ALL that Heat out the exhaust. Matter of fact.....I think Headers loose more heat into the Engine Compartment than the Stock Exhaust Manifolds given they are individual pipes.

Your situation regarding NOT overheating at idle in 100 deg F must be attributed to the Header Coating and your Higher Flow Rate Spal Fans I would say.

Thanks for the Information......:thumbsup:

[Fully Vetted]

I dont get concerned until after 240



Thank you for that tidbit. I've been reading this and wondering at what point do I start looking for a place to park.

[tf95ZR1]

Anyone played with heat extractors to help get the underhood heat out?

I know this is a radiator thread and don't want to hijack, but
"heat extractors" was brought up. A radiator is a heat extractor,
but I also found that my high rise hood helped reduce temps.
Not only more room above the engine, but vents in
front of the windshield.

[Hog]

I know this is a radiator thread and don't want to hijack, but
"heat extractors" was brought up. A radiator is a heat extractor,
but I also found that my high rise hood helped reduce temps.
Not only more room above the engine, but vents in
front of the windshield.
On the 99-2002 SLP Firehawks, there were 2 vents at the corners of the hood at the windshield end. When the electric fans were running, you could place your hand over these "heat extractors" and feel warm air coming out of them.
I'm sure this would be more pronounced at speed.
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Cars3/slpfirehawk_zps3c490903.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Cars3/slpfirehawk_zps3c490903.jpg.html)

Did you notice lower coolant temps or underhood temps?
Were your vents akin to a cowl induction hood?

My thoughs are that at a stop of slow speed, a "cowl induction" style of vent would work well, but at speed the high pressure area at the base of the windshield would lose its effectiveness. It seems that most guys have issues while idling around, so a hood like yours sound good.

While at speed, you dont even need fans as the natural airflow across the rad is more effective.

[Hog]

Thank you for that tidbit. I've been reading this and wondering at what point do I start looking for a place to park.

Since the OEM calibration doesnt enable the 2nd fan until 234º you should be good.
My 98 STS had a similar very high 2nd fan enable temp, it was difficult to get that fan to engage from temps alone.

Thats the nervous point, do I drive faster and try to cool the engine?, or do I pull over in some shade? Pulling over and shutting down will not cool like I want it to.

[Hog]

Ya......after my experiment idling in 100 deg F .....with AC On and then AC Off....opening the hood did drop the temperature a couple degrees......With Headers I think it would be worse under the hood.

I have no clue how one would direct heat coming through the Oil Cooler, AC Condenser, and Radiator downward under the engine and somehow directing cool air above the engine except a new hood design with louvers.



Doesnt most of the air go down and under the car normally? If so, I wonder how the lowered cars do thermally as compared to the stock height cars.
I would think that no one change would affect cooling substantially, however a few minor changes could cumulatively affect cooling. A leaf in the rad, a waterpump with some cavitation damage could be enough to cause overheating.

I wonder how much of a difference underhood heat actully makes? After the air comes through the rads it has done its job in removing heat from the rad/coolant/engine, then lets say it does get hotter from the headers, is that really going to cause the engine itself to run hotter? Perhaps if teh engine is actually ingesting the heated air through the air intake, but normally its not.
Does bathing the outside of the engine in hotter air, cause it to run substantially hotter.

I know that the selling point of ceramic coating is to control heat transfer. Its usually to keep heat inside the exhaust in order to keep its velocity high, or to prevent thermal damage to nearby components.

Stock exhaust manifolds are no example of a part that runs cool. They are thick and heavy and radiate heat like a monster, but they are durable, as such are used by OEM's.

I can see a worse case scenario going something like some WOT driving on a hot day, then coming upon stop and go traffic. Air/con off, windows down, heater on revs at 1500rpm, hope for the best.

Interesting discussion for sure.

For those in the SouthWest where its hot and bone dry, does anyone run their central airconditioning with water misting on the condensor coils outside of their homes? Ive heard of this, as well as water spray cooling for those tile roofs.
This adds evaporative cooling to the system. If anyone runs water injection on their car, a nozzle could be used for emergency cooling on their car. Obviously not a good idea if you are injecting methanol.