Small Block in an early A - how much room for a fan?
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"
radiator thickness (mounting surface of radiator yoke to engine side of core): 2 3/4"
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"
Late water pump depth: 5 1/2"
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.
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".
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"
radiator thickness (mounting surface of radiator yoke to engine side of core): 2 3/4"
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"
Late water pump depth: 5 1/2"
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.
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".