sloopy
2-digit whp
- Joined
- May 25, 2020
- Location
- Dallas, Texas
I'm planning my high-compression b230 sugmotor build and need some help making some decisons about my cooling system. I live in Texas, so I really want to do this right.
I figure it might be a good idea to get a new radiator since mine is old. I'm assuming the stock radiator is sized big enough. So should I stick with the stock nissens with plastic end tanks, or are those all aluminum radiators a better option? A drop-in replacement which utilizes the stock mounts, isolators, and hoses would be ideal. And thinking about an oil cooler, (mine doesn't have one as far as I'm aware) would it be worthwhile to try to use a radiator with the automatic transmission oil cooler to cool my engine oil? Or would it be better to use the stock turbo oil cooler or even a universal oil cooler mounted in front of the condenser?
Now thinking about the fan; Currently, I have a mechanical cooling fan plus the little electric pusher in front of the condenser. I want to convert to an electric cooling fan and ditch the mechanical fan and the electric pusher. STS machining sells this e-fan setup (https://www.stsmachininginc.com/products/e-fan-set-up-for-redblock-240-740-volvos-1975-1993) which uses a spal 16" single-speed fan. Potentially, I could control the fan speed via pwm. I'm not sure if I should be concerned about introducing a bunch of noise into the electrical system (thinking about the ham radio and the stereo system). I also don't really know how I would accomplish it. I'm sure my maxxecu race can be programmed to control the fan using a pwm output, but I guess I would need some sort of mosfet or something to power the fan because a mechanical relay will not be able to handle pwm speeds. Another option is using a volvo 850 fan which is also 16" but has two speeds. This would allow me to use volvo's nice little relay and power distribution brick. I don't know much about how the different speeds are used in practice though. I guess I would have two temperature thresholds which would trigger the two different speeds. I guess I would also use a digital input on the maxxecu connected to the a/c switch or something which would trigger either the low-speed or high-speed fan output.
Once I make a decision on all of that, I need to figure out what I want to do about the shroud. I've seen some people mount the electric fan right up against the radiator without a shroud. Seems like a very simple setup which allows the best airflow at speed, but limits the cooling ability of the fan. Or, like the STS machining shroud (and all of the oem shrouds) there are flaps in the shroud which get sucked shut to allow the fan to pull air through the radiator, but will allow more passive airflow through the radiator at speed. Another interesting setup I've seen is using a plain shroud without the flaps, but the shroud doesn't span the whole width of the radiator which would allow more passive airflow at speed. I like the simplicity of this, but not sure of the impact on cooling at idle. Theoretically, the fan is pulling air through all of the cooling channels, but not across the whole width of them.
I figure it might be a good idea to get a new radiator since mine is old. I'm assuming the stock radiator is sized big enough. So should I stick with the stock nissens with plastic end tanks, or are those all aluminum radiators a better option? A drop-in replacement which utilizes the stock mounts, isolators, and hoses would be ideal. And thinking about an oil cooler, (mine doesn't have one as far as I'm aware) would it be worthwhile to try to use a radiator with the automatic transmission oil cooler to cool my engine oil? Or would it be better to use the stock turbo oil cooler or even a universal oil cooler mounted in front of the condenser?
Now thinking about the fan; Currently, I have a mechanical cooling fan plus the little electric pusher in front of the condenser. I want to convert to an electric cooling fan and ditch the mechanical fan and the electric pusher. STS machining sells this e-fan setup (https://www.stsmachininginc.com/products/e-fan-set-up-for-redblock-240-740-volvos-1975-1993) which uses a spal 16" single-speed fan. Potentially, I could control the fan speed via pwm. I'm not sure if I should be concerned about introducing a bunch of noise into the electrical system (thinking about the ham radio and the stereo system). I also don't really know how I would accomplish it. I'm sure my maxxecu race can be programmed to control the fan using a pwm output, but I guess I would need some sort of mosfet or something to power the fan because a mechanical relay will not be able to handle pwm speeds. Another option is using a volvo 850 fan which is also 16" but has two speeds. This would allow me to use volvo's nice little relay and power distribution brick. I don't know much about how the different speeds are used in practice though. I guess I would have two temperature thresholds which would trigger the two different speeds. I guess I would also use a digital input on the maxxecu connected to the a/c switch or something which would trigger either the low-speed or high-speed fan output.
Once I make a decision on all of that, I need to figure out what I want to do about the shroud. I've seen some people mount the electric fan right up against the radiator without a shroud. Seems like a very simple setup which allows the best airflow at speed, but limits the cooling ability of the fan. Or, like the STS machining shroud (and all of the oem shrouds) there are flaps in the shroud which get sucked shut to allow the fan to pull air through the radiator, but will allow more passive airflow through the radiator at speed. Another interesting setup I've seen is using a plain shroud without the flaps, but the shroud doesn't span the whole width of the radiator which would allow more passive airflow at speed. I like the simplicity of this, but not sure of the impact on cooling at idle. Theoretically, the fan is pulling air through all of the cooling channels, but not across the whole width of them.
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) You need to fab some upper radiator brackets but the lowers are already perfect when you move the right side rubber bumper into the original hole for the airbox. for the airbox I am running a cut in half 240 airbox pushed in sideways where the battery used to be but I am looking for something else as I am measuring a ~3kpa drop pre-throttle body and think it is a restriction. I haven't yet installed the 940 e-fan so I have the original mech fan without a shroud, but that got me through summer dd duty without a single temp issue. (coastal masshole climate, perhaps)