Bulletproof cooling system
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(→Bulletproof cooling system tips: Spelling; clean up) |
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*You should use a radiator at least as large as the one that was originally used to cool the engine (not the car) from the factory, and with the same or more radiator cores. However, it's important to note that additional rows of radiators don't add a proportional amount of cooling: a 3-row radiator does not offer 50% more cooling than a 2-row radiator. This is because subsequent rows receive warm air from the rows in front of them. However, adding radiator frontal area IS proportional, but this usually causes fitment issues, so additional rows are generally the only viable choice. | *You should use a radiator at least as large as the one that was originally used to cool the engine (not the car) from the factory, and with the same or more radiator cores. However, it's important to note that additional rows of radiators don't add a proportional amount of cooling: a 3-row radiator does not offer 50% more cooling than a 2-row radiator. This is because subsequent rows receive warm air from the rows in front of them. However, adding radiator frontal area IS proportional, but this usually causes fitment issues, so additional rows are generally the only viable choice. | ||
*Oftentimes, the cheapest and most bulletproof way is to use the largest radiator that will fit, along with the shroud that was designed for the radiator from the factory and the designated steel fan and viscous drive assembly for same. ''(confirm and expand)'' | *Oftentimes, the cheapest and most bulletproof way is to use the largest radiator that will fit, along with the shroud that was designed for the radiator from the factory and the designated steel fan and viscous drive assembly for same. ''(confirm and expand)'' | ||
| − | *Use a full shroud, with the radiator positioned so that the fan blades are half-in and half-out of the shroud hole ''(confirm and expand)'', and no more than 1" of clearance between the shroud and the fan blade tips. (Just enough to prevent | + | *Use a full shroud, with the radiator positioned so that the fan blades are half-in and half-out of the shroud hole ''(confirm and expand)'', and no more than 1" of clearance between the shroud and the fan blade tips. (Just enough to prevent interference when the motor rocks on its rubber mounts). |
*Fan recommendations: OEM 18 inch, 7-blade steel fan with 2" to 2-3/4" pitch. Pitch of a fan can be measured by laying the fan down on a flat surface and measuring from the flat surface to the edge of the fan blade. Fans that are relatively flat (such as a flex fan) won't move enough air at idle and low engine RPM to do the job properly. | *Fan recommendations: OEM 18 inch, 7-blade steel fan with 2" to 2-3/4" pitch. Pitch of a fan can be measured by laying the fan down on a flat surface and measuring from the flat surface to the edge of the fan blade. Fans that are relatively flat (such as a flex fan) won't move enough air at idle and low engine RPM to do the job properly. | ||
*Thermostatically controlled fan clutch. | *Thermostatically controlled fan clutch. | ||
| − | *Water pump and crankshaft pulleys sized according to what was on the engine from the factory. On a street motor, shoot for 1.2 to 1.3 times crank speed for pump pulley speed. This is usually true until you get to 3.55 gears and numerically higher, then 1 to 1 works better. Most 1960's muscle cars are 1 to 1. | + | *Water pump and crankshaft pulleys sized according to what was on the engine from the factory. On a street motor, shoot for 1.2 to 1.3 times crank speed for pump pulley speed. This is usually true until you get to 3.55 gears and numerically higher, then 1 to 1 works better. Most 1960's muscle cars are 1 to 1. Sustained pump speeds over 4200 rpm can cause cavitation. Race vehicles may use a 3.5" crank pulley with a 8" water pump pulley for a 9000-plus rpm engine. |
*On a carburetor-equipped engine, most of us use a 180º thermostat, although a little hotter thermostat (190º-195º) may make the motor more responsive and add a little fuel mileage. It may also help to burn off some of the by-products of operation, such as moisture and acids which form and get into the oil. Motors using EFI induction should be operated at the temperature specified by the factory for that particular motor to prevent false input to the computer and consequent problems. ''(confirm and expand)'' The sensor pill goes toward the motor. | *On a carburetor-equipped engine, most of us use a 180º thermostat, although a little hotter thermostat (190º-195º) may make the motor more responsive and add a little fuel mileage. It may also help to burn off some of the by-products of operation, such as moisture and acids which form and get into the oil. Motors using EFI induction should be operated at the temperature specified by the factory for that particular motor to prevent false input to the computer and consequent problems. ''(confirm and expand)'' The sensor pill goes toward the motor. | ||
*Use a spiral-wound spring in the bottom radiator hose, to prevent collapse of the hose. | *Use a spiral-wound spring in the bottom radiator hose, to prevent collapse of the hose. | ||
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*Although it may not be necessary, the concept of a "water pump conversion disc" is intriguing. Flow Kooler originally marketed flat aluminum discs to rivet to the backside of the stamped steel impeller in the pump. With an iron impeller, a steel disc could be welded or brazed onto the impeller. The disc wouldn't be that difficult to make. Space the water pump backing plate back farther with a couple of gaskets to prevent interference of the rivet heads on the backing plate if riveting a disc to a stamped steel impeller. More info: [http://www.smokstak.com/forum/showthread.php?t=11774 brazing cast iron], [http://store.summitracing.com/partdetail.asp?part=BRA%2D4375%2D07&autoview=sku Flow Kooler water pump conversion discs]. This disc should make an appreciable difference in the flow of water at engine speeds under 3,000 RPM. On the other hand, Howard Stewart of Stewart Components (the guy with the water pump dyno), says that the disc's have little to no effect. | *Although it may not be necessary, the concept of a "water pump conversion disc" is intriguing. Flow Kooler originally marketed flat aluminum discs to rivet to the backside of the stamped steel impeller in the pump. With an iron impeller, a steel disc could be welded or brazed onto the impeller. The disc wouldn't be that difficult to make. Space the water pump backing plate back farther with a couple of gaskets to prevent interference of the rivet heads on the backing plate if riveting a disc to a stamped steel impeller. More info: [http://www.smokstak.com/forum/showthread.php?t=11774 brazing cast iron], [http://store.summitracing.com/partdetail.asp?part=BRA%2D4375%2D07&autoview=sku Flow Kooler water pump conversion discs]. This disc should make an appreciable difference in the flow of water at engine speeds under 3,000 RPM. On the other hand, Howard Stewart of Stewart Components (the guy with the water pump dyno), says that the disc's have little to no effect. | ||
| − | '''NOTE:''' While a thermostatically modulated fan clutch is an effective means of operating the cooling system's fan, a worn or defective fan clutch can cause overheating yet go undiagnosed. Sometimes they will appear to be OK when cold but they will free-wheel when hot! | + | '''NOTE:''' While a thermostatically modulated fan clutch is an effective means of operating the cooling system's fan, a worn or defective fan clutch can cause overheating yet go undiagnosed. Sometimes they will appear to be OK when cold but they will free-wheel when hot! |
==Swapping a core support and matching radiator into a recipient vehicle== | ==Swapping a core support and matching radiator into a recipient vehicle== | ||
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