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  Topic Review (Newest First)
05-13-2020 03:40 PM
Big Dave Pick-up trucks used a 20" inch diameter fan because they have a LOT more under hood room for a bigger radiator. I used a pick-up truck radiator in my '85 Impala by dropping the bottom radiator mount down two inches to get the hood to close. It allowed me a bigger radiator to cool a bigger motor.

With even a high performance (high horse) SBC you should have no difficulty getting the stock radiator width and height to cool your engine; just adding additional depth in terms of added rows of radiator core to handle the added heat load (stock two row copper/brass radiator for a base SBC; and a three row copper/brass radiator for a high performance engine or a stock one with A/C. If you need to go to a four core copper/brass radiator (used with a BBC and A/C) it is an option.

Big Dave
05-13-2020 02:48 PM
BA. The fan in that picture does certainly look too big in diameter to fit within any shroud. Like someone said, perhaps an attempt at better cooling when the real solution is to first get a shroud in place. At this point, it looks like you'll need both a fan and a shroud.
05-13-2020 08:38 AM
Brooksey Thank you, I would be interested in that if it would work ok with the 350 engine.I am located 14020 between rochester and buffalo
05-13-2020 08:10 AM
Deadwolf I'm not sure where you are at, but I probably have an extra stock fan, shroud, and old radiator set aside here around Grand Rapids Michigan. That is if your interested in taking it back to stock. Out of a 283 SBC car with automatic transmission.
05-12-2020 07:29 PM
Brooksey Installed fan guard. I tried to install the complete shroud I bought but it didnt fit the radiator. Took everything apart but still no go. Used only the top part of the shroud. This should keep it safe for the hands.
11-28-2019 07:24 AM
wk2hons I had the same problem on my 67. I put in a new aluminum radiator, then went to a junkyard and found an electric fan that would fit ( I took a sketch of the space that I had). It keeps the engine running cool. I always keep an eye on the temp gauge.
11-27-2019 07:32 AM
Big Dave As Pete stated your radiator is short for a full size car. It may have been sourced out of a mid size or a compact car which has a smaller radiator due to restricted space (why it is so hard to cool a BBC Camaro). I used a radiator out of a BBC light truck which is bigger than an Impala radiator to cool my maximum sized (for a standard deck height) BBC.

If you look at a Semi truck you see the size radiator that is required for a 350 horse engine (that is all the horsepower an in line six diesel will have on average, though a semi has many other engine options up to a V12 available to it if you don't mind buying a lot more fuel to get you to the same spot). That is why a Semi can idle all night long and not over heat. With radiators bigger is better.

Big Dave
11-26-2019 10:12 PM
Brooksey Thanks friends, I ordered the shroud, sure hope it fits well with my existing radiator
11-26-2019 09:10 PM
Originally Posted by Brooksey View Post
It has a 7 blade clutch fan about 17 inches dia and it sticks about 1/2 inch above the top of the radiator
The new pics are better.

As compared to an OEM installation, the fan is not too big, the radiator is too 'short' for it (and it does not have a shroud).

What you 'fix' (I would not leave it as is; I'd saw something off) depends on how 'original' you want the car to look. Either 'fix' can be made to cool the engine.

Big Dave gave some good advice regarding the expansion 'tank'. The OEM radiator is 'tall' enough to have room (internal to the radiator) for expansion above the internal 'fins' (no external expansion tank; just a overflow tube). It is also 'tall' enough for the 17" fan. The radiator is filled only to cover the fins. Filling to the 'top' may cause nuisance overflows.

An alternative is a radiator with an external expansion tank that can be 'shorter'. Both work.

He is also right about the 4 blade fan. Because I was getting some temps I did not like at idle, I switched to this:

I rarely get above 190 (I have alum heads) and never above 200. The engine is always kept in proper timing.

11-26-2019 07:46 PM
Big Dave You will want a fan shroud off of a 1969-'99 Impala to cover the exposed fan blade.

Big Dave
11-26-2019 06:07 PM
Brooksey It has a 7 blade clutch fan about 17 inches dia and it sticks about 1/2 inch above the top of the radiator
11-26-2019 04:10 PM
sz0k30 Some much better pictures would help. In one photo all I see is engine and no fan. In the second I barely see a fin tip.
11-26-2019 03:40 PM
Big Dave You can find a shroud to fit your fan in a junk yard. it will be made of fiberglass plastic (sans cloth to reinforce the resin). It doesn't have to come off of a GM product (though I would look there first). It just has to fit under your hood and to enclose the front half of the fan. So you will need to know the fan diameter. For a GM gas engine it should be 18" in diameter. The more blades you have the quieter the fan will be and the more air it will move.

Modern air liners have curved up wing tips for the same reason your house fan has a blade shaped like the wing of a Spitfire WWII fighter plane. Air slides off the end of a fan blade or an air plane wing unless constrained by a fan shroud, a winglet or a counter aerodynamic force in the case of the Spitfire. Old four blade fan blades are stamped out of flat metal and twisted so they act like a canoe paddle when it comes to moving air (take a moment to imagine the paddle of a canoe moving through the water).

You can see the vortices coming off the paddle as you pull on it. Modern more expensive paddles are made of plastic with hollow metal shafts and have a cupped blade to capture the water.

On a five bladed clutch fan (used on A/C equipped cars) have a bent tip and an arc in the blade to capture the air instead of letting it slide off. I used a seven blade clutch fan to keep my 582 BBC cool on Central Florida streets during the summer. If you have ever been to Disney World in the summer you will know that it is a wet heat that is oppressive. Your car feels the same way and needs help staying cool.

Big Dave
11-26-2019 02:17 PM
Originally Posted by Brooksey View Post
I just got a 1960 2 door that has a replacement 350 engine. The fan blade sticks up higher than the radiator which I think is dsngerous. It works fine though. Any suggestions from some experienced friends to fix this are welcome
It appears a previous owner installed a larger fan in an attempt to make up for the missing shroud. Not what I would have done. A shroud is my preferred installation but it requires the fan blade to be properly located within it. Approx 1/2 in, 1/2 out is correct.

If you are going to work on the car, I strongly recommend you acquire the shop manual and the assembly manual. They are great soures of reliable information.

In general it should look something like the attached pic of my '63. It shows a std 4 blade fan. The 5 blade clutched fan install is different but the placement of the blade in the shroud is the same.

Hope this is helpful.

11-25-2019 08:02 PM
Big Dave Your car originally had a tank on the top and bottom of the radiator. It appears you have a more modern cross flow radiator installed now (tanks on the ends of the core). Even so all V8 engines and six cylinders with A/C used a fan shroud to duct the air through the radiator. It is the fan shroud (and possibly the FORD decal that says" Caution Fan) that protects your fingers from being sliced off by the fan blade.

Big Dave
11-25-2019 07:11 PM
62BillT Your car is supposed to have a Fan Shroud, but it looks like you no longer have the original Radiator. If the car runs cool enough the way it is, just install a smaller Fan Blade. Keep an eye on the Temperature though.
11-25-2019 05:06 PM
high clutch fan blade

I just got a 1960 2 door that has a replacement 350 engine. The fan blade sticks up higher than the radiator which I think is dsngerous. It works fine though. Any suggestions from some experienced friends to fix this are welcome

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