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Discussion Starter #1
So I'm getting ready to plumb the lines for my trunk tank and decided how I want them based on my reading on here. However I'm a bit concerned about air getting trapped so tell me what you think about this routing.
Trunk tank to pump( stock location ZR1)
Pump to upper lid
lower lid to Vadder HX
HX back to tank

Will dropping into the top of the lid cause problems and will it push the air though the system back to the tank?
 

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What will that help?
You will be pushing the water the length of the hose instead of trying to pull it out of the tank.
 

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Discussion Starter #5
The pump is still the lower point so the tank will gravity feed it. I do have the option to run a Rule in the tank also but didn't want to due to reliability.
 

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The pump is still the lower point so the tank will gravity feed it. I do have the option to run a Rule in the tank also but didn't want to due to reliability.
Yes, but in general pumps work better pumping the distance rather then pulling the distance.
 

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Discussion Starter #7
The pump still remains a gravity fed pump its not a puller so will it really affect how it works based on it's location as long as it has a good supply of water?
 

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The pump still remains a gravity fed pump its not a puller so will it really affect how it works based on it's location as long as it has a good supply of water?
Well maybe it will. What will happen to the gravity feed under WOT?
 

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Discussion Starter #10
The outlet is on the back of the tank so under WOT the water is pushing towards the back correct? I'm just trying to get a handle on how moving the pump will help I'm not opposed to moving it but it needs to be a logical worthwild venture.
 

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You have pressure loss every foot of hose, you also have additional loss for every elbow or turn of the hose. Then, on top of that, if you are racing, or accelerating hard, you have that acceleration working against the 'column' of water in the hose, the entire length of the hose.

So, you may or may not get a void in the line, but you certainly are not helping the pump by asking it to pull the water up against the friction of the hose plus the acceleration of the car.

You want the pump to push the water, not have to suck the water. If you had a diaphragm pump, I would be less concerned, but these are not diaphragm pumps.
 

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Discussion Starter #13
That makes sense thanks for the input. Anytime I run any sort of lines I aways try and limit the amount of turns and when they are needed use long sweeps to aid the flow. So will pushing down though the brick and HX work without trapping air?
 

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I’m not sure what you mean.

If you don’t introduce air after you bleed it properly, you should be fine.

Gravity feed the pump, tank above it, don’t let the tank run low. Gravity and velocity help get the air out of the lines and brick.

Ideally, you bleed out the air at the high point of the loop.


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Discussion Starter #15
When I was running the under hood tank everything pushed up though the brick and into the tank which was the highest point. Now I would be pushing down though the brick to get the iced water there first then though the HX. So that would put the brick as the highest point now. Will all the air eventually push it's way out of the system pushing down instead of up?
 

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With the ZL1 lid, not sure if you are running it, it’s above the underhood tank, fwiw.

That being said, you can get the air out the way you said, it just may take longer to bleed.

What I typically will do is block the flow at the upper hose for a few seconds, then slowly (10 seconds or so) open it up, using a hose pliers or even a clamp or similar.

By slowly opening it, you are giving the bubbles a chance to race ahead of the water. Think of molecules and inertia. Less inertia, the higher acceleration, which means increase velocity (air to liquid velocities).

The air bubbles tend to cling to the hose, so you have to overcome that friction. Once you do, it’s a race to the finish, but a closed loop has no finish ;)




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Discussion Starter #17
I'm routing lines today and I came to the conclusion the routing is easier this way=
Trunk tank to lower HX port (Pump in trunk now!)
Upper HX port to lower lid port
Upper lid port back to tank

I know this route will eliminate any trapped air however if I decide to ice which will be not often it will go though the HX first. Is this a terrible route or no? It will keep the lines neat also so they are not looping back and forth.
 

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It's kinda a trade off thing. For street use the routing you listed is best. For icing at the track it's not the best because you will heat the water some. Now how much that makes a difference is debatable.
 

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I'm routing lines today and I came to the conclusion the routing is easier this way=
Trunk tank to lower HX port (Pump in trunk now!)
Upper HX port to lower lid port
Upper lid port back to tank

I know this route will eliminate any trapped air however if I decide to ice which will be not often it will go though the HX first. Is this a terrible route or no? It will keep the lines neat also so they are not looping back and forth.
I get what you are trying to do as far as routing and keeping it clean, but typically a HX (like your radiator) is set up to have the water dropped in from the high side so it is cooling as it falls to the pump which then you will push it directly to the lid. So you may not get as much temp drop pushing it up through the HX, I'd be in for your findings though. And yes you are correct, pushing ice water to the HX will defeat the purpose of the ice. Now if you can have a track set up where you switch the hoses around and even delete the HX for track runs only you would have better luck with temps IMO. good luck !
 

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Discussion Starter #20
Went I had the under hood tank I still pushed water up though the Vadder's and it averaged 10-15 degrees above ambient and recovered from a hard pull in 45 seconds. I know this route keep air from being trapped. To be honest the car has not seen the track yet in 3 years as sad as it is just don't have time! So it's basically a local cruise car when I find time!
I think street driving the coolest water will be coming out of the HX when ice is not involved and with the additional water/pump combo it should move allot to make a difference.
 
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