Small Block in an early A - how much room for a fan?

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halfafish

halfafish

Damn those rabbits, and their holes!
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I'm gathering parts to put a small block in a 64 Valiant. For anyone who has this combo, can you give me a measurement for how much depth you have for a fan, from the water pump flange to the radiator? I'd like to run a clutch fan but I don't have a way to measure this ahead of time.
 
halfafish said:
I'm gathering parts to put a small block in a 64 Valiant. For anyone who has this combo, can you give me a measurement for how much depth you have for a fan, from the water pump flange to the radiator? I'd like to run a clutch fan but I don't have a way to measure this ahead of time.
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Are you running the early (short) cast iron water pump or the later (longer) aluminum pump?
And what radiator? Some of the newer aluminum radiators are notoriously thicker than the factory radiators, and have mount brackets that space the radiator a considerable distance from the yoke. And even the factory radiators can vary in thickness a bit.
If it will be comparable, I can get you a measurement tomorrow of a late LA water pump to a factory '70 radiator in a '66 Dart.
 
If you run the early water pump I believe the standard clutch fan will work, later water pump/timing cover you may need the 2947 from Hayden.
 
Professor Fate said:
re you running the early (short) cast iron water pump or the later (longer) aluminum pump?
Click to expand...

Time for a confession. Me + Slants = reasonably well informed. Me + Small Block = mostly clueless. I didn't know there was a choice of early/late for water pumps. The core engine is in a 74 Dart but it needs a thorough go-through so if it fits I can use the early water pump. The radiator is a Summit 22" that is not all that thick - it's about the same as a 2-row stocker. I can get a measurement on the radiator tomorrow after work. The clutch fan I'm looking at is 3-3/8" deep from flange to front of clutch.

Professor Fate said:
If it will be comparable, I can get you a measurement tomorrow of a late LA water pump to a factory '70 radiator in a '66 Dart.
Click to expand...

I would appreciate the help when you get time.
 
Back in about '75/76 somewhere, I had this oil burning slanty in a 65 Valiant wagon. and I had this junkyard 340 short, with a missing cam, and
I had a top-end and cam from a 69 Satellite 318,
and an early 273 complete with a 904.
With very little effort I installed that big-bore-318/904 with the front end off that 273, and it's engine brackets; and Smooth as butter it slid right in there. I had a lil entertainment with the gas pedal, and she needed fenderwell headers. But the cooling system was a bolt-together deal, with the 273 pump..
IIRC I reused the slanty direct drive 4-blade fan, and the slanty rad.
That was a hot lil column shift combo, until the 273 automatic packed it in.
Gave it to my lil brother about a year before he got his license, in about '77/78.
The deal was, that he would put a different slanty into it, with the original 904, and I would get back whatever was left over. I still got that junk, lol.
 
About 3 inches. This champion radiator is thick also. Dustin.

IMG_0225.jpeg
 
I had a 360 in a 65 Valiant years ago with a stock radiator re-cored with a four row core by a local radiator shop and I had the Mopar Viscous Fan Package on it. It was tight, but it fit.
 
keep in mind that the early waterpump exits driver's side and the late waterpump is pass side.

this is important for radiator hook up and timing cover. you can't see the timing tab with the pass side outlet in the way. plus, the the mark on the balancer coincides with the timing cover, which not the end of the world, you can always re-mark it.

so really it's more about matching the radiator, if you already have one.
 
Just my 2 cents...

64 had a 273 ( small block) option. If you collect all the STOCK parts it will fit in without any issue.

Now toss in an aftermarket AL rad (not needed) and clutch drive fan (not needed) and you are in for a time.


Find a stock 64 small block radiator have it recorded with AC or HD cooling core. Be sure it has drivers side outlet on the bottom and drivers side inlet on the top.


Get a pass side bolt on timing mark

Get a 64 to 69 cast Iron water pump if going with an AC / HD cooling water pump be sure your pullies match. Standard cooling was most likely under driven by 10 percent or so. AC / HD would be overdriven

Get a fixed 7 blade fan, look for AC / HD cooling part number.

This way EVERYTHING will work as the engineers designed AND in the future getting replacement parts will be simple
 
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I get 4 inches for my 65 Barracuda, original radiator with replacement three row core, 71 340 motor with early style short water pump and 273 timing cover, damper and pulleys as shown in Posts # 9 and #10 above.
 
Okay, as promised- pics and measurements of a '66 Dart with a late aluminum water pump and a stock '70 HD radiator, engine mounted with stock (but modded for a 360) 273 motor mounts (so you know it is positioned correctly), all measurements are approximate and as close as I could eyeball the tape measure.
Radiator core to water pump pulley: 2 5/8"
1721335832155.png

radiator thickness (mounting surface of radiator yoke to engine side of core): 2 3/4"
1721335909815.png

Now for some generally useful measurements (but these will require math, you have been warned!).
Timing cover (both early and late are the same thickness) water pump surface to radiator yoke: 11"
(Sorry, no pic)
Early water pump depth: 4 3/4"
1721335955678.png

Late water pump depth: 5 1/2"
1721336005915.png

Total height of viscous fan and clutch: 2 1/2" - I used the shortest number out of 4 units I had on hand, they ranged from 2 1/2 to 3 1/2 inches, with two of them being 3", which I believe to be the standard passcar unit. The 3 1/2" one I believe came off a truck.
1721336111141.png

How are these measurements useful?
Well, we know we have approximately 11" from the timing cover to the radiator yoke; so we need to fit a water pump, fan assembly, radiator, and enough fan to radiator clearance into that measurement.
In my instance, I had about 2 5/8" left for a fan assembly and running clearance. A 2 1/2" viscous fan leaves me 1/8" clearance, not enough by any means. So I went with a rigid fan and a spacer to get me between 3/4" and 1" clearance.
If I had run a shorter early iron WP, that would have gained me another 3/4" of clearance- which would have been enough to run the clutch fan. My other option would have been a thinner radiator, such as was used on later ('73-'76?) A bodies, which were about 3/4" thinner than what I've got, which would have been about right for the clutch fan again. But long story short, I ran what I had- and it works.
So measure up your radiator thickness, add the height of whichever water pump you intend to use, and add 3/4" to 1" of running clearance. Whatever that number is will tell you if you've got enough room to run a 2 1/2" clutch fan within your allotted 11".
 
halfafish said:
I didn't know there was a choice of early/late for water pumps.
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Early pumps exit on the drivers side for the lower radiator hose
Late pumps exit to the passenger side
Question is, where is the lower hose fitting on your radiator?
The Hayden short shaft clutch fan mentioned above is readily available and a real problem solver and not too pricey.

The early and late pumps also have different placement of the timing marks, so if the donor engine is a 74 and you are using the original harmonic balancer, the timing mark would be WAAAY off if used with an early pump.
 
At 2.71" overall height, the Hayden 2947 is still too tall to work in many combinations.
At one time, @slantsixdan had mentioned a Mercedes unit that was even shorter than the Hayden, but I forget the exact application.
 
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Professor Fate said:
At one time, @slantsixdan had mentioned a Mercedes unit that was even shorter than the Hayden, but I forget the exact application.
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Good call. I have this info somewhere, and I have one of these fans squirreled away in Parts Mountain.

Thanks to all for the good info. I will file this for use when I get closer to putting this together.
 
str12-340 said:
The early and late pumps also have different placement of the timing marks, so if the donor engine is a 74 and you are using the original harmonic balancer, the timing mark would be WAAAY off if used with an early pump.
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it's the timing cover that has the marks cast into it, not the pump.

on 68 and earlier engines there was a timing tab that bolted to the front of the pump.

due to the outlet, using the later pump on the earlier cover obscures the tab or marks, so you would need to re-mark it on the other side or somewhere visible to set the timing.
 
If I'm understanding things right you can put the early water pump on the later timing cover. I've read elsewhere the poly engine pumps are also an option don't know how true that is
 
halfafish said:
Good call. I have this info somewhere, and I have one of these fans squirreled away in Parts Mountain.

Thanks to all for the good info. I will file this for use when I get closer to putting this together.
Click to expand...
"Parts mountain ".... BAHAHAHAHAHAAAA....
 
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