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Discussion Starter · #1 ·
Ok here is my question is it better to mount the fans in the engine compartment or will it matter if they are outside pushing the air through the radiator? I've been contemplating this for the last month since I'm making my own setup, because I'm poor and I can wire anything. I'd think the pusher style would be better but it would be more noticeable from the front..

Has anyone ever just used the stock water pump with a 12v motor running it, I know there are kits that do this for real race cars but i want to drive this on the street also.. I don't want to put a meziere pump on it due to cost and if it fails other problems would arise. I want to build a setup that I can dial in an exact temp I want the truck to run at and between the pump, the fans and adding more capacity to the intercooler tank and fans on the intercooler radiator combination the engine would be at the same temp for every run.. I'm planning on running a dual battery setup if you're wondering where all this power will come from.

I'm open to all suggestions, flames here's your chance Rob, [smilie=popcorn.gif]
 

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is it better to mount the fans in the engine compartment or will it matter if they are outside pushing the air through the radiator?
Since I'm the cooling guy I'll take this one.. ;)

It does'nt really matter assuming that the fan is snug to the rad.  There is one down side to placing it in front.  Debris over time will plug up the electric motor.

stock water pump with a 12v motor running it
It would'nt be too smart.  However if you did.. I'd take a 8 blade pump (stock on the 99s and all V10s) and spin it at about 2500rpms at speed. And at about 1000 rpms at idle. (All stock pumps spin 1.3 times faster than crank rpms)


Ok having said all that.  As a water pump engineer I can tell you that doing it that way your giving up a significant amount of energy. Since this is'nt a 1/4 mile king and your wanting to do street drivng... I'd suggest just sticking with a 7 blade truck pump.

Rich
 

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Discussion Starter · #3 ·
I can tell you that doing it that way your giving up a significant amount of energy.

I don't understand what you mean by that.?

It's good to know about the RPM's! I was thinking in the line of tracking the rpms and matching them with the rpm's of the pump with a sensor on the crank.. The pump motor won't be your everyday 12v motor it will be a synchronous and will provide rpm feedback so i can setup a feedback loop in the controls.

Is the 7 blade truck pump different than what we already have?
 

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Oh I just saw you have a 01. Your stock pump is what I'm talking about.

Energy: There are losses in trying to create electricity and then turning that into a mechanical rotation and then using that rotation in pumping fluid. That's all I'm trying to say. With an electrical motor your introducing at least 2 areas of energy consumption that are not currently there.

The stock 7 blade really is'nt costing you much in the way of power. Ive not done a study to see how much hp is freed up by driving the pump w/a seperate motor? But assuming your running the juice off the alt.? It is pretty much null.
You see, these water pumps are not linear in power consumption. They are close to nothing at idle.. but when the pump speed reaches approx 2000rpms the torque needed is higher. AND THEN it depends of whether the stat is open or not. (cavitation does crazy things)

Sorry about rambling.. To sum it up. Your gonna spend an awfull lot of money and shorten the life of the motor to gain maybe 3hp at best. IMO there are only a handfull of lightings out there that would want to bother with this level of "bang for the buck".

Rich
 

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Discussion Starter · #5 ·
I understand what you're saying, but horsepower isn't what I'm after, it's consistency. I'm also turning the alternator off when I'm in a race and the fan and pump motors will be supplied by the battery setup, so there will be no lost power due to the extra load on the alternator while I'm actually on the 1/4 mile. After the run I'll turn the alternator back on and recharge in between rounds.. In my layman opinion it will decrease the number of heat cycles to the engine if it works right and should prolong the life of the engine. You know a hell of a lot more about it than I do and I appreciate the info! Anything else you can tell me I'd appreciate it. Thanks Rich!
 

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Sounds like you know know what your after.

One thing I will point out. The water velocity sweeps the gas bubbles off of the cylinder and head walls in a studied and therefore understood manner. Hence the degass bottle you see on all the modular motors. If you look at the hose routing it'll make sense that this is'nt just a overflow or purge container. It takes the bubbles out of the system and allows for a greater control of delta Ts by supplying a mostly fluid media back to the motor.

If your gonna do like you say with the variable speed? Then definately get yourself a 8 blade pump w/a 102mm diameter impeller. (was stock on the 99s) 1000 rpms at idle and it won't need to go over 2500-3000 rpms max. (Any rpms beyond that and it's being starved by the block anyway) I'd ramp it to 2000 rpms at cruising/towing speeds and then have it hit 3000 at say 5000 crank rpms.

Rich
 

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Discussion Starter · #7 ·
Ok I have another question if the normal pump runs at 1.3 times the rpm of the engine at 5000 rpm it would be turning at 6500 rpms. Why would I want to limit the rpms of the pump to 3000?

one more question since I'm picking your brain and by the way I owe you a dinner at your favorite McDonalds......
If the velocity of the water is what knocks the outgassing bubbles loose from the cylinder walls and the cannister basically degasses the water is there anything else I can do to help this out, for better cooling?
 

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Why would I want to limit the rpms of the pump to 3000?
I can't let the kat out of the bag here. Ford paid for all this info I'm dishing out at that particular answer is... :-? Just trust me that over 3000 rpms *on the 8 blade imepller* your not gaining anything. (e-mail me if you want the scoop)

is there anything else I can do to help this out, for better cooling?
The most effective thing you can do is to cool the fluid going to the IC under the blower. Other areas really are'nt significant gains. They might help a little.. bit it's slim pickens so to speak. Oh.. and you can always check to see that the system pressure is at spec. (16 psi I think it is?) The lesser the pressure the more likely gasses form.

Rich
 

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wydopnthrtl said:
is it better to mount the fans in the engine compartment or will it matter if they are outside pushing the air through the radiator?
Since I'm the cooling guy I'll take this one.. ;)

It does'nt really matter assuming that the fan is snug to the rad.  There is one down side to placing it in front.  Debris over time will plug up the electric motor.

stock water pump with a 12v motor running it
It would'nt be too smart.  However if you did.. I'd take a 8 blade pump (stock on the 99s and all V10s) and spin it at about 2500rpms at speed. And at about 1000 rpms at idle. (All stock pumps spin 1.3 times faster than crank rpms)


Ok having said all that.  As a water pump engineer I can tell you that doing it that way your giving up a significant amount of energy. Since this is'nt a 1/4 mile king and your wanting to do street drivng... I'd suggest just sticking with a 7 blade truck pump.

Rich
Good thing we live in the same state! I am going to need your help Rich with my cooling set up. Looks like I will be ready in about a week.

I'll e-mail you.

Suavy
 

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Don't forget that elec fans pull more CFM than they Push. So pull is usually better, especially for a truck.
 
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