Smaller radiator for FE?

[99LeCouch]

A poor man's way of testing this would be to remove your t-stat, blocking off half the radiator via removable aero mods (think cardboard and masking tape), and driving a test loop doing some A-B-A testing. B would be normal. Make sure to monitor coolant temperatures.

[Christ]

Hell, I was just going to remove the T-stat after getting a timed baseline for how long it took to idle up to temp, then start periodically putting in smaller radiators until either I started overheating under my normal driving, or I met the time goal.

In Civics, the half sized radiator works every bit as good as the full sized, but I've seen reports of faster warm-up times, partially due to lowered cooling capacity, but also partially due to less coolant to heat up/cool down for each cycle.

[Frank Lee]

T-stats represent a fairly large restriction to flow, even when open fully, which loads the water pump.

I believe this whole premise to be incorrect.

When you reduce volume pumped by restriction, the load on the pump gets EASIER, not harder.

Example? Take a hairdryer and turn it on. Note the speed. Now block the flow completely. It speeds up! It wouldn't speed up unless the load was reduced.

[Christ]

The thermostat only blocks flow to the radiator. It comes after the pump, and after the flow through the engine block. If the thermostat is closed, the coolant recircs through the block, then back through the water pump.

If the thermostat is open, the coolant proceeds through the water pump, through the block, through the thermostat, then into the radiator, and back to the water pump.

Because the circuit is built the way it is, you're looking at it backwards. The thermostat is a restriction to pressurized hot fluid, and doesn't contact the cooled fluid returning from the radiator to the water pump.

Therefore, instead of choking off the input of the hair dryer, as you suggested, you'd have to test the theory by blocking the output of the dryer (or box fan), which does actually place a load on it, because it's trying to compress a fluid. (Air, in this case.)

[Old Mechanic]

An adjustable radiator or grille block that maintained the coolant temperature of the coolant exiting the radiator at the same level it was in summer would help a lot with improving mileage in the winter.

regards
Mech

[Frank Lee]

Yeah, block the output. I didn't specify inlet or outlet. It doesn't matter. Grab that hairdryer and do it. Turn the heat off if you can; it gets damn hot!

[Old Mechanic]

I remember Basjoos has a light that tells him the electric cooling fan is running. If it runs often he opens his adjustable air inlet.

With that kind of aero and engine compartment sealing he is getting hot coolant outflow and warm air intake, without anything else.

regards
Mech

[Christ]

Originally Posted by Frank Lee

Yeah, block the output. I didn't specify inlet or outlet. It doesn't matter. Grab that hairdryer and do it. Turn the heat off if you can; it gets damn hot!

K, so without a thermostat, I'd be able to use a smaller radiator, since there would still be more flow, regardless of whether it's loading the water pump or not. Smaller radiator = less fluid to pump, which DOES partially unload the water pump, and less weight (granted, miniscule amount) that the engine has to propel when moving the vehicle, plus another measure of aero benefit.

Granted, all miniscule compared to leaving the t-stat in, but still gains to be had. On top of all that, no worrying about the Tstat failing closed. Not supposed to happen, but it does.

[Frank Lee]

I've no problem with the 1/2 rad concept- a lil lighter, etc.

I don't think the pump will "see" any difference re: volume in the system. Forget about pump loading.

Thermostats regulate temp and improve warm-up times. I am not aware of any data that says they are the limiting factor in cooling system capacity. They rarely fail... or I'm just lucky? Bwaahahahaha!!! I don't see any benefits to disabling them.

[Christ]

I've had two fail in my life. Thinking about it, I'm not really sure why I wanted to go with no Tstat. I don't think it had any premise based on real thought, rather than just going on a whim, saying (yup, I'd like to remove that thing).

I guess goals don't really need a reason, just an end and a means, right?