Would a shroud for my electric fan help my cooling problem?
I've got an '80 z/28 with a flattop 468, northern alum. radiator,be-cool/spal 16in. fan, stewart stage II alum. hi flow water pump, stewart hi flow 180* thermastat. Temp. out on the open road got up to a little over 215* last week. Some say that is not hot, but makes me alittle uncomfortable. I catch myself watching the temp. gauge more than the road. Has not overflowed yet, but I would like to keep the temps. down.
Before I spend the money ($100 custom shroud from cool craft) would this keep my temps down?

Thanks, :confused:

Any time you can direct the air flow from the fan it should help the cooling of the motor. In my opinion the shroud and fan do not do much for the cooling of the car over 30-40 mph. If you have cooling problems at highway speeds you have different problems than just controlling the air flow from your fan. Could your temp guage be off? I have heard in some cases of the hi flow water pump causing problems. It circulates the coolant through the radiator so fast that it does not have time to cool it down.

I had almost the same set up w/a 16" electric fan (1680cfm) and was running at 200-220 area and like you said your always watching the temp gauge. Last Friday I removed the ecectric fan and put a 18" Derale fan on my water pump using a spacer along w/ a 180 degree thermostate. Not wanting to get rid of the electric but after installing this, I let my car idle in driveway and drove all over the place and never got over 180 degrees....however I am using my fan shroud and like I said I just did this last friday so not awhole lot of driving since I made the change.

Here is my experience. I have a small block car the motor is fairly tame.
For almost 10 years I ran it with the stock 3 row rad. no shroud and
a junk thin blade flex fan. On the road no mater what temp. it was out side it never got over 190. When in traffic at slow speed it would climb, how far I do not I never let it get past 210.This past weekend I installed
a shroud and Taurus 2 speed fan, the shroud covers the whole rad. the
only opening is the 16" hole for the fan. Now sitting still in traffic on a
80 plus day the temp went down to 170 to 180 with a 180 stat. on the
slow speed only. But on the road where I had no problem before it runs
200 with the fan on and more with it off. I feel the fan and shroud block
to much air at speed. So now I need to drill large holes in the open areas
of the shroud too let air thru at speed and find a way to block them at rest.
My guess is your fan is blocking air flow at speed.

Here is my experience. I have a small block car the motor is fairly tame.
For almost 10 years I ran it with the stock 3 row rad. no shroud and
a junk thin blade flex fan. On the road no mater what temp. it was out side it never got over 190. When in traffic at slow speed it would climb, how far I do not I never let it get past 210.This past weekend I installed
a shroud and Taurus 2 speed fan, the shroud covers the whole rad. the
only opening is the 16" hole for the fan. Now sitting still in traffic on a
80 plus day the temp went down to 170 to 180 with a 180 stat. on the
slow speed only. But on the road where I had no problem before it runs
200 with the fan on and more with it off. I feel the fan and shroud block
to much air at speed. So now I need to drill large holes in the open areas
of the shroud too let air thru at speed and find a way to block them at rest.
My guess is your fan is blocking air flow at speed.


I agree with old blue.

By the way old blue, what did you use for your shroud? I currently have a MK8 mounted with the stock shroud up against the core & I am running into the same issues. I put some holes & flaps in the shroud but I dont think they are large enough.

Thanks,
Shane

I agree with old blue.

By the way old blue, what did you use for your shroud? I currently have a MK8 mounted with the stock shroud up against the core & I am running into the same issues. I put some holes & flaps in the shroud but I dont think they are large enough.

Thanks,
Shane


Shane I bent up a shroud out of .090 alum. at work. It was about an
1.25" out from the rad. then i took the Taurus fan and cut the stock shroud down. It has a step in the middle of it so I cut the bottom step off. If i would not have done that there would not have been room to fit it past the water pump. It also looks better this way. When I mounted it I turned it 90 deg. for a better look.:bowtie:

p.s. does yours cool going down the road with the fan on?

Thanks for the feedback so far. I guess i'll try to fab. something up like old blue 75 said, before I buy one. I also have a cut off switch for my fan, I'll try killing it also next time out on the highway. I'll keep trying till I get it to work..

p.s. does yours cool going down the road with the fan on?

NO! That is the problem Im having as well. It is not a terrrible situation, it will idle at 190 or so, all day. Driving at a moderate speed, say 30-45 is starts creeping up, and on the highway it will climb up towards 225-230.

Most stock fans shut off around 25-35 MPH that is why im thinking it is flow problem. Right now the MK8 shroud covers all but 1.5" on one side & about 2" on the other. These edges sit behind the core support so I dont think Im getting great airflow through the edges of the core, like I hoped they would.

Take care,
Shane

Just a quick question. What do you guys have for hoods on your cars?
The reason I ask is if you have a stock flat hood there may not be enough
air flow through the engine compartment to create low pressure behind the rad. I have a 3" cowl hood on mine open in the back you can really feel the heat escape through the opening. Some other ideas , rad. cap pressure,pump pulley dia. amount of anti -freeze in the coolant,rad. size & type.

I just recently built a shroud for mine, see it here:
http://www.nastyz28.com/forum/showthread.php?t=95744

I've had it out on the highway for long trips and sitting still idling in 100*+ Texas heat for extended periods of time, hottest I've seen it get is 170* so far.
I was going to add flaps to the closed areas of the shroud if it acted like it was going to heat up on the highway, but after last weekends trip I'm convinced it will be just fine as is.

I just recently built a shroud for mine, see it here:
http://www.nastyz28.com/forum/showthread.php?t=95744

I've had it out on the highway for long trips and sitting still idling in 100*+ Texas heat for extended periods of time, hottest I've seen it get is 170* so far.
I was going to add flaps to the closed areas of the shroud if it acted like it was going to heat up on the highway, but after last weekends trip I'm convinced it will be just fine as is.

great info David...:)