Reverse cooling - how to?

[niceguynick50]

Hey guys. You'll probably laugh at me, but I want to try and set up my Twin turbo 302 Ford efi with reverse cooling and figured I'd ask all of you "NASA types" what you would recommend. I would like to use some type of mechanical water pump and have been looking into some of the pumps used in marine boating engines. It would ideally be a remote mounted mechanical set up to push the water into the intake/thermostat location and then come out at the previous location where the original water pump used to push it into the block. I would then use a "boating style" thermostat housing to bring the the 2 sides back together, meet the thermostat and send it back the radiator. I know you're probably laughing now, but I'd really like to try it. Any ideas or suggestions are GREATLY appreciated. Nick

 

[Bigcat]

There has been some use of reverse flow cooling. GM did it on certain engines with apparent success. Cooling the heads first makes a great deal of sense as it is where most of the heat is generated and one could expect a faster warm up of the block to operating temperature. Here is a website that explains the GM system:

http://www.e-toolbox.com/application/8852/8852CH09_How_the_Cooling_System_Works.htm

Better make sure you plumb it carefully to eliminate steam pockets in the heads or you will have big problems. I recall that 302's may have a gasket restriction as designed that might require some well thought out modifications.

 

[wildbill805]

Use an electric water pump that is a two fold plus you save the HP of not have to drive the pump with a belt and you can flow the water in the direction that you are looking for. The reverse flow is a good way to help in detonation. Electric water pumps have come a long way and they are reliable.

 

[patprimmer]

The electric water pump, especialy if thermostatically regulated is a very good thing, but it is not quite true to say that it is not belt powered, as the electricity used to power it is generrated by a belt driven alternator, which will eventually consume more power than the direct belt driven water pump to pump the same amount of water.

Regards
pat

 

[drwebb]

Why is an electrical water pump an automatic efficiency debit? Part of the motivation for 42V electrical systems is so that ALL accessories could be electric, and hence more efficient.

 

[GregLocock]

Alternators are typically much less than 60% efficient (40 would be more like it). Cheap electric motors are 60% efficient at best. Pumps are around 40-70% efficient. Belts are around, what 90-95% efficient?



Cheers

Greg Locock

 

[patprimmer]

I didn't say that it was an automatic efficiency debit, I said that you cannot presume that it will be a credit just because you remove the direct belt drive. An electric water pump is still belt driven, abeit by indirect means which further reduce the efficiency. There might be gains as if it is well controlled with a thermostat, a lot less water might actually be pumped.
The biggest waste in a belt driven pump is not the belt drive, but the fact that it is running all the time the engine is running, and in a fixed relationship to engine speed, not thermal load

Regards
pat

 

[ZoRG]

Belts aren't that efficient, especially the more common V belts, this is why alot of the newer cars come our with vvv belts, tiny v's(5 of them) almost flat ... flat belts are the most effecient @ 90%... your standard car V belt is problably in the area of 60% efficient.

The bonus with a electric pump is that it pumps the correct amount of water, on a mechanical system when the engine reaches +-3000rpm, the pump is at its limits, from there on its just a waiste of energy.

I have an electrical pump on one of my cars and it works like a charm, you can not really notice the extra load from the alternator, however you do notice the extra power from removing the mechanical pump, so it does not matter how effecient what is, it still works better, only problem is it is a bit expensive, and does not always last as long as mechanical pumps do.

 

[wildbill805]

Remember guys he wanted to reverse the water flow this was not a study of energy consumption! The belt maybe 90% effective but you have the drag of the impellers in the water which steals HP from the engine the electric pump is a constant load if you have a concern with the power of the alternator drag put a larger alternator on and under drive the alternator.

 

[niceguynick50]

Thanks for all of the great input guys. My first idea WAS to use an electric motor, but now I'm leaning towards a mechanical. It will definitely be easier to plumb an electric setup and will probably save me like 20 or so flywheel horsepower, but for some reason I feel that they won't be as reliable as a mechanical. This car is supposed to be capable of daily driving and reliability is a major concern. I know that there are many reliable electric water pumps out there to. I have heard that their flow rates drop very quickly in relation to pressure compared to the mechanical units. I don't know, maybe I should just use an electric pump and see what happens. It would make things alot simpler for now. I have also scanned Grainger's website and see a few pumps that would do the trick for a very reasonable price. I plan to just push the water into the intake at the thermostat mounting point, but ideally water would be pushed directly into the heads and the intake would be a "dry" design. I tell you what. Why don't we have a vote and I'll choose that way Thabnks again guys, Nick