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Discussion Starter #1
since fitting a stronger motor in the 66 this year i've been struggling to keep the temp down, it was borderline with the last engine, recently changed the 1-1 ratio pullys to the march overdrive items but it still ran hot, (220 in traffic and still rising) payed a visit to a local mopar guy that runs a 68/440 dart who also had cooling issues and solved his by running a factory mechanical fan and no shroud, he dug out a chevy factory clutch fan to try, fitted it without a shroud, the difference is night and day, had it idling with the hood shut for around 45 min on a fairly warm day and it sat at 160deg, highway driving or traffic does'nt seem to make any difference, it stays around 160, ok i may cost hp but a least i've car that at last stays cool, heres the combination,

26" x 19" northern rad, 160 stat, edelbrock water pump, march high flow/overdrive pullys, factory 5 blade clutch fan approx 19.5" diameter.

seems the electric fan shroud was maybe trapping the air?

old combo.


new combo. (i will paint the ugly fan)

 

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Which direction does that electric fan spin? Clockwise?
 

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Discussion Starter #3
as you look at the photo it spins anti clockwise, it was wired to pull the air which it did well, i think its rated around 2000cfm.
 

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For what my thoughts are worth... The fan shrould looks like it is to much restriction even with the vent. I would assume the flaps on the right close when the fan is sucking air at idle? Just make sure they don't leak and air comes in around them which would bypass the radiator.
Also, I don't think 2000 cfm is enough. I ran a 2000 cfm single fan unit and could not keep temps under control. I upped to a dual 11" which is 2980 cfm and things are much better but still borderline on hot days.
A lot of guys have sucess with the tarus setup.
It is still hard to beat a mechanical setup.
Tg
 

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Discussion Starter #5
i've got to agree that the shroud probably is too restrictive, i'd guess that the fan needs to be further away from the core with a more tapered shroud, a local guy with a 68 firebird w/427 b/block runs a taurus without problems, the manufacturers invest a small fortune designing cooling systems with mechanical fans that have to work in 120 desert heat with the air con blowing, i'm sure that if a lot of the guys with cooling problems went back to the factory set up they would have more success.
 

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Just out of curosity, is that a long or short water pump. I converted to a long pump last year so I could run a low mount a/c bracket. Have thought about switching back to a mechanical fan but not sure I have room:eek:
Tg
 

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I don't understand everybody talks, you got to have a shroud, then ya all say the shroud is to restrictive. Whats up with that . Look at all the custom shrouds they cover the radiator like the one in the pic. No real cure here. Shroud or no shroud.
 

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Discussion Starter #9
Just out of curosity, is that a long or short water pump. I converted to a long pump last year so I could run a low mount a/c bracket. Have thought about switching back to a mechanical fan but not sure I have room:eek:
Tg
i'm running a long water pump, theres around 3/4" gap between the fan clutch to the rad core, the rad has twin 1" tubes, a non clutch fan would give more clearance,

(cell phone pic)
 

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I don't understand everybody talks, you got to have a shroud, then ya all say the shroud is to restrictive. Whats up with that . Look at all the custom shrouds they cover the radiator like the one in the pic. No real cure here. Shroud or no shroud.
You don't absolutely need a shroud. They just make the fan more efficient. It's not like your car is guanteed to overheat without one. '64 V-8 Novas never had one from the factory. It's always nice to have one but what this exercise proves is that a mechanical fan with no shroud puts more air flow through the radiator than the electric fan with the restrictive shroud did.

I would stick with the mechanical fan and add a shroud to make the set-up even better than it already is. The only time I run an electric fan is when I can't fit a mechanical one in.
 

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I don't understand everybody talks, you got to have a shroud, then ya all say the shroud is to restrictive. Whats up with that . Look at all the custom shrouds they cover the radiator like the one in the pic. No real cure here. Shroud or no shroud.
The shroud will offer the best cooling if it's funnel shaped and allow the fan to draw air from the complete rad.The one posted is tight on the pass side with the flaps that will open at speed,but at idle the fan can't draw air from the whole rad cause the shroud is tight to the rad.
 

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The stock 64 v-8 radiator and fan and shroud were adequate. Thats because it was only a 283 with about 150 H.P. Not a good comparison since most of us are running minimum 350 cu.
 
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