My Cooling Improvement Project (hopefully)
CHAPTER 2 - Crank and Water pump Pulleys
The next thing I changed was the crank and water pump pulleys.
I did this to try to get back as close as possible to the factory pulley ratios.
According to the information on this site:
http://www.bouchillonperformance.com/BPEpulleys.asp
The factory single groove crank pulley is 6 9/16" and the single groove water pump pulley is 6 7/8".
This is a pulley ratio of .95 to 1.
With a crankshaft speed of 1000 RPM the water pump RPM is 1047.62.
The pulleys I had on the engine were:
Crank Pulley Diameter = 6 7/8" or 6.875" and Water Pump Pulley Diameter = 4 3/4" or 4.75"
This combination has a Pulley Ratio of .69 to 1 or a water pump speed of 1447 RPM.
I THINK the water pump speed was too high and not allowing the coolant to stay in the radiator long enough.
I had spare crank and water pump pulleys that are both 5 7/8" which is a 1 to 1 ratio.
At a crank RPM of 1000 the water pump will be 1000 RPM or about 47 RPM slower than stock. I am hoping that slowing the coolant flow thru the system will help lower the engine temps.
CHAPTER 2 - Crank and Water pump Pulleys
The next thing I changed was the crank and water pump pulleys.
I did this to try to get back as close as possible to the factory pulley ratios.
According to the information on this site:
http://www.bouchillonperformance.com/BPEpulleys.asp
The factory single groove crank pulley is 6 9/16" and the single groove water pump pulley is 6 7/8".
This is a pulley ratio of .95 to 1.
With a crankshaft speed of 1000 RPM the water pump RPM is 1047.62.
The pulleys I had on the engine were:
Crank Pulley Diameter = 6 7/8" or 6.875" and Water Pump Pulley Diameter = 4 3/4" or 4.75"
This combination has a Pulley Ratio of .69 to 1 or a water pump speed of 1447 RPM.
I THINK the water pump speed was too high and not allowing the coolant to stay in the radiator long enough.
I had spare crank and water pump pulleys that are both 5 7/8" which is a 1 to 1 ratio.
At a crank RPM of 1000 the water pump will be 1000 RPM or about 47 RPM slower than stock. I am hoping that slowing the coolant flow thru the system will help lower the engine temps.
