Chevy Nova Forum banner

1 - 20 of 26 Posts

·
Vendor
Joined
·
7,085 Posts
Discussion Starter #1
\

This is what I have on my car currently and it runs warmer than my old mechanical fan/shroud combination.I am looking for opinions/flaws in this design.It gets hot at freeway speeds and it looks to me as though the design will greatly reduce air flow at high speeds.I am considering adding an opening above and below each fan to increase air flow at speed.I am wondering if I should add a rubber flap to the opening to help the fans at low speed or just add vents.I have seen OEM manufactures go either way.
 

·
Vendor
Joined
·
7,085 Posts
Discussion Starter #3 (Edited)
I think it is a 180 high flow thermostat,185 fan switch.Temp sender for the gauge is in the rear of the intake. fan sender is in the front of the intake where the stock temp sender was..Fans come on @160 on the gauge and the car runs @200 on the hiway on a hot day.
 

·
Registered
Joined
·
362 Posts
I run an aluminum set up with aluminum shroud and top cover on the radiator. I have 2 1" cors and a cross flow design with one SPAL 2360 CFM Fan instead of two smaller ones. I don't run any flaps in the shroud and I too have a 180 thermostat, as well as a SPAL fan control that comes on at 185 and goes off at 165. my car goes down the road or sits in traffic at just a tick over 180. I also have a high flow aluminum water pump. Is your motor pretty much stock or is it modified?
 

·
Premium Member
Joined
·
256 Posts
I purchased a similar unit like this and found that the SPAL fans 11" pulled less than 1600 CFM total..Not enough to cool the motor down..They were listed for 2300 CFM and mine did the same thing except I had vents in the aluminum shroud.. I called SPAL and they said that the information listed from the vendor was incorrect...

You might want recheck with the fan company and see what they tell you..Before you cut up your shroud...

Eddie
 

·
Registered
Joined
·
3,859 Posts
\

This is what I have on my car currently and it runs warmer than my old mechanical fan/shroud combination.I am looking for opinions/flaws in this design.It gets hot at freeway speeds and it looks to me as though the design will greatly reduce air flow at high speeds.I am considering adding an opening above and below each fan to increase air flow at speed.I am wondering if I should add a rubber flap to the opening to help the fans at low speed or just add vents.I have seen OEM manufactures go either way.
Brian, I would add the rubber flaps that way they suck closed at low speed and force all the air to be pulled through the radiator, on the freeway they will be blown open by pressure built up in the shroud and allow more air through the radiator. Just adding vents would help on the freeway but would cause the car to run warmer around town. BTW the set-up looks trick, what a bummer that it dose'nt work properly for you.
 

·
Premium Member
Joined
·
2,858 Posts
I was having same issues with Taurus fan set up. My water pump was underdriven, and my water pump was not pumping enough water. Changed pulley and went to a high flow water pump. Now stays at 180 with fans on low, in traffic or when hard on her. No fans needed on highway.
 

·
Premium Member
Joined
·
236 Posts
brian,
here's my set up that i was describing to you, i think your radiator is wider than mine so you might not have to "modify" it like i did. i'm not sure if this will even work, but it has the flaps you are mentioning. theres one thing about my set-up that i need help with:
you will see in the pics that there is a gap at the top and bottom of the fan (area between fan shroud and radiator core). i'm concerned that air will get sucked thru this area by the fan instead of air being pulled thru the radiator.
ANY SUGGESTIONS WOULD BE MUCH APPRECIATED!!!!!!
i have tried putting weatherstripping to fill the gap, and also (not in pics) i cut 2 small strips of aluminum and mounted it to the fan braces.....this way will work (i think) it just doesn't look very good.

http://i407.photobucket.com/albums/pp158/434ChevyII/fanpics007.jpg
http://i407.photobucket.com/albums/pp158/434ChevyII/fanpics006.jpg
http://i407.photobucket.com/albums/pp158/434ChevyII/fanpics002.jpg
http://i407.photobucket.com/albums/pp158/434ChevyII/fanpics001.jpg
 

·
Premium Member
Joined
·
4,176 Posts
If it is getting hot on the road and not in traffic. Then you need the flaps so more air can get out of the shroud. You must have a dead spot not letting air move. I see it a lot when they make it to flat and don't put any slope in it. I use to use a smoke machine and a high speed fan to find them. When I found it or them I would cut a 1" hole and she would cool right down.
 

·
Vendor
Joined
·
7,085 Posts
Discussion Starter #10 (Edited)
The motor is 530 hp small block.It has a Meziere mechanical water pump and as recomended by them the water pump pulley is slightly smaller than the crank pulley so it is not under driven.I had an underdriven set up and it was just the same.12-1 compression with aluminum heads.Griffin aluminum radiator with two rows of 1 1/4 tubes.It does have a large trans cooler in front of the radiator.It has an advertised 5k stall converter that will push the car foot braking at around 3k.Spal's web site says each fan pulls 2310 CFM if I am reading the spec's correctly.
 

·
Registered
Joined
·
566 Posts
Add an oil cooler. They kick *** at speed ( more air flow ) and do less at idle, so it should totally fix your problem. cool oil is a good thing anyway.
 

·
Vendor
Joined
·
7,085 Posts
Discussion Starter #12
I have considered this but where do you put a decent size oil cooler on an early Nova.The only space I have is where the battery was,I could cut a hole and add a cooler with a fan/s.Also running -10-12 braided linecould also be an issue due to space.
 

·
Premium Member
Joined
·
4,613 Posts
Brian- hinged flaps should solve the problem. At Derale, we call it dead-heading. Meaning, the air coming into the radiator at freeway speeds does not get evacuated due to the electric fans not speeding up enough to meet the inrush of air. Your local ACE hardware store sells a little three pack of various assorted gasket materials in the plumbing section. One of the sheets is black rubber. You can cut it into any desired shape to fit certain areas of your shroud. Pop rivet it on. Also, if you still need a oil cooler, go onto Derale.com If you see something, let me know. I've tested just about every one of them.
 

·
Registered
Joined
·
397 Posts
3DTim said:
... When I found it or them I would cut a 1" hole and she would cool right down.
A 1" hole provides enough cross-sectional area to allow sufficient air flow? In the picture provided drilling numerous 1" holes would solve the air flow problem? I guess it doesn't necessarily require a "rubber gasket" to act as a one-way flapper? So I have to wonder - since I am getting ready to do a very similar install - is the shroud necessary at all - short of providing a way to mount the fans? I mean, the shroud could almost be swiss cheese right? In essence that's what tubbed63 has done with the louvers. Just trying to understand so I only design mine once. Thanks. -Bob
 

·
Vendor
Joined
·
7,085 Posts
Discussion Starter #18
Finally got a chance to find an OEM type shroud venting sollution.I found the simple little rubber flaps on a Volvo 960.









We will see if this help out the dead heading of air though radiator at hiway speeds.
 
1 - 20 of 26 Posts
Top