Watercooling hoses through longs?, I need feedback from those who've done it. Options

[BMITCHELL]

mine, never got around to puting the rockers on.

[Katmanken]

I looked at those, I've had enough engineering classes in thermodynamics to at least be cautious of the 90 degree bends. I'm going to go out to the garage and take another look at where he put those hoses through.

Maybe it can be done with some gentler bends behind My AP speaker pods.

(IMG:style_emoticons/default/blink.gif)

Seriously, a couple of things to consider. Aluminum is one of the better conductors of heat which is why it's used for oil coolers, heat sinks and the like. Rubber on the other hand doesn't conduct heat nearly as well. I'd stick to the rubber unless you really like heat.

Can you explain the 90 degree bend heat change?

[ruby914]

I looked at those, I've had enough engineering classes in thermodynamics to at least be cautious of the 90 degree bends. I'm going to go out to the garage and take another look at where he put those hoses through.

Maybe it can be done with some gentler bends behind My AP speaker pods.

(IMG:style_emoticons/default/blink.gif)

Seriously, a couple of things to consider. Aluminum is one of the better conductors of heat which is why it's used for oil coolers, heat sinks and the like. Rubber on the other hand doesn't conduct heat nearly as well. I'd stick to the rubber unless you really like heat.

Can you explain the 90 degree bend heat change?

If you went rubber mounted aluminum tubes under the car heat could be released to the air and the pan would be insulated. I would think best of both worlds.

[ruby914]

mine, never got around to puting the rockers on.

That is what I am thinking is next for me.
The back looks easy.

[Cracker]

If you went rubber mounted aluminum tubes under the car heat could be released to the air and the pan would be insulated. I would think best of both worlds.

As a rule...you do not want exposed "hard" tubing under the car. Should you run over something or have an off road excursion, aluminum, steel tubing crushes (and doesn't come back). Rubber compresses then... ;-)

[ruby914]

The front is harder. Only after I replaced this lower A pillar from PO A/C install, I consider taking a hole saw to it. But I would weld a tube through the hole for the hose or a smaller tube to go through. The socket in the photo is the stand in for the smaller tube.
After that there is a sharp bend to stay clear of the tire...

[ruby914]

If you went rubber mounted aluminum tubes under the car heat could be released to the air and the pan would be insulated. I would think best of both worlds.

As a rule...you do not want exposed "hard" tubing under the car. Should you run over something or have an off road excursion, aluminum, steel tubing crushes (and doesn't come back). Rubber compresses then... ;-)

(IMG:style_emoticons/default/agree.gif) And I want my car lower.

[ruby914]

Here is the headache bend that needs to clear the tire.
If this was prebent SS tube I think it would work.
I may be talking with friends over at FMF motorcycle racing to bend the SS tube.

[Mike Bellis]

At this point, you should go up and into the top of the fender. Drop down next to the headlight. Add a petcock at the high point to bleed.

Make a set for me too... (IMG:style_emoticons/default/biggrin.gif)

[pktzygt]

I looked at those, I've had enough engineering classes in thermodynamics to at least be cautious of the 90 degree bends. I'm going to go out to the garage and take another look at where he put those hoses through.

Maybe it can be done with some gentler bends behind My AP speaker pods.

(IMG:style_emoticons/default/blink.gif)

Seriously, a couple of things to consider. Aluminum is one of the better conductors of heat which is why it's used for oil coolers, heat sinks and the like. Rubber on the other hand doesn't conduct heat nearly as well. I'd stick to the rubber unless you really like heat.

Can you explain the 90 degree bend heat change?

90 degree bend heat change......blah blah......laminar flow.....blah blah.....turbulent flow.... blah blah..... not exactly a quick explanation, but what I meant to say is that the thermodynamics classes I have taken include a professor rattling on about fluid flow and how the turbulence created through a 90 degree bend reduces flow. Fluid flow is what I getting at, not heat transfer. But yes, it can make a difference in heat transfer too.

Sorry about the confusion, my mind was elsewhere as I was typing that earlier (2 kids).

[DBCooper]

But yes, it can make a difference

How much difference? Enough to go through all the convolutions you're seeing that alternate routing will require? Isn't it a question of trade-offs? So how much difference will those 90 degree turns make, really? The reason i ask is that it works on a lot of cars that are actually driving around out there.

My hoses go underneath and my car is way way too low. I've hit them a number of times and no problem so far, but I have peeled the hose clamps back on the hose, so I wasn't far from screwing things up. I don't have shift linkage in the tunnel any more so am thinking that's probably the best option for my car, but can't have the heat in the cockpit problem. I drive the car a lot and it can't be hot. I guess A/C would fix that, so maybe that priority just got higher, but it just seems too posh.

[pktzygt]

But yes, it can make a difference

How much difference? Enough to go through all the convolutions you're seeing that alternate routing will require? Isn't it a question of trade-offs? So how much difference will those 90 degree turns make, really? The reason i ask is that it works on a lot of cars that are actually driving around out there.

My hoses go underneath and my car is way way too low. I've hit them a number of times and no problem so far, but I have peeled the hose clamps back on the hose, so I wasn't far from screwing things up. I don't have shift linkage in the tunnel any more so am thinking that's probably the best option for my car, but can't have the heat in the cockpit problem. I drive the car a lot and it can't be hot. I guess A/C would fix that, so maybe that priority just got higher, but it just seems too posh.

Well, it's been done so I'm sure it can work. I'd put money on it not working as well than if the bend was reduced. I personally still like the idea of some kind of hose or pipe running down the tunnel with some pipe insulation on it.... think roll cage padding.

For now I'll take the quick and easy route and re-evaluate later. Maybe I'll bump the thread when I try something new.

On a side note, I bought the A/C system from renegade. It is a fairly quick and easy route for sure, but I expect it to work well. I'm not pulling out the factory venting because eventually I will put a heater core in the vent box and some sort of A/C system that won't like it should be under the dash of a Jeep CJ.

[skeates]

I'm in the process of doing a suby conversion myself and have elected to route the coolant line through the longs. I haven't gotten too far yet, but from some brief mock-ups I don't think that you loose enough cabin space for average size people to notice.

I'm not too worried about the additional pressure losses by having the two additional near 90 degree bends in the hose. Especially since I will be running 1.5" and 1.25" hose (a little bit bigger than stock suby hose as I understand it). The increased diameter will help to reduce the pressure drops introduced by the bends. While I have the longs open I plan on installing some insulation on the passenger compartment side of the coolant hoses to help encourage the heat to transfer away from me. BTW, the whole thing will be designed to facilitate (relative) easy removal and installation of the hose, so serviceability shouldn't be a problem.

One solution I considered (but elected not to implement because of the work) was to cut open the bottom length of the longs and then weld in a piece of 3" tubing that I would cut in half like a clam shell. This would give the hose a nice hidden length to run while keeping it exposed to the air for cooling. But to do this I figured that I would have had to open the top of the long afterwards and install some gussets to maintain the long's rigidity. You might be able to squeeze out a 5 degree drop in you water temps from the added cooling when traveling at freeway speeds and running finned tubing instead of rubber. I originally wanted to do this in an effort to reduce the size of my radiator and free up room in the front trunk. But after running the calcs I figured that I wouldn't be able to squeeze out enough cooling capacity from the finned tubes to make it worth the investment in effort.

[pktzygt]

Ohh yeah, I forgot to mention. A/C isn't posh in VA, people think i'm crazy driving my CRX with no A/C even after I tell them that I get over 50mpg.

I'm going to have A/C for those days beach tourist traffic makes my commute miserable. I'm in the Navy and my uniform is not exactly breathable.

[pktzygt]

Yeah, Skeates. I'm not too worried about the cooling capacity with the subaru motor and the renegade cooling. I've never heard any issues with this setup unless someone screwed something up like swapping the inlet and outlet hoses.

I'm not going to cut open my longs for much more than getting the hose in the front of the long. Have you seen the threads where the door gaps get messed up. I'm not opening that can of worms. I'm hesitant to even put an engman kit on it.....yet.....

[Mike Bellis]

This craigs list car has someone's attempt at tunnel cooling with aluminum pipe.
http://sfbay.craigslist.org/sby/cto/2912092744.html

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[Andyrew]

^^ What a great way to heat up the fuel.

Pretty obvious they never finished it..

[bulitt]

Has anyone used rectangular tubing on the bottom? I'm sure the turbulence would be terrible but a 5/8"x 2.5" would probably suffice and would hug the floor. Would need round tube welded on the ends??
Also if you have radiators in the front and want AC where does the condenser mount? is there still room left on the floor for the condenser? What does that do to the rigidity of the front end with holes in both the wheel wells and the floor?

[Cracker]

Yeah, Skeates. I'm not too worried about the cooling capacity with the subaru motor and the renegade cooling. I've never heard any issues with this setup unless someone screwed something up like swapping the inlet and outlet hoses.

I'm not going to cut open my longs for much more than getting the hose in the front of the long. Have you seen the threads where the door gaps get messed up. I'm not opening that can of worms. I'm hesitant to even put an engman kit on it.....yet.....

Sean,

You bring up two interesting points. First, you will have no problem with cooling if the renegade cooling kit is the same for both the LS/Subie options. I actually run to cool - their system is extremely efficient.

DOOR GAPS
The rockers and longs are thin and it doesn't take much at all to start screwing up gaps. Been there done that when welding in a cage and the plates were attached to the inside rockers (without sufficiently "hanging" the body). It all was corrected perfectly but I AM STILL AMAZED AT HOW FLIMSY THE 914 CHASSIS IS - my car is a relatively rust free example too!!! Be careful with the longs/rockers!

The other thing that makes things tight up front for cooling hoses is the gas tank, steering rack, MC location and having in/out on same side of rad. I ran my hoses neatly down the two belly pan reliefs (front-to-rear), then over the rack, through the shock tower divider side by side.

Since this is a long post...I might as well continue at this point. What I plan to do and might be of help to someone in the future is: 1) Build 6 gussests that will compress the hoses slightly vertically (egg) and taper out on either side. Think of these as skid plate protectors for the cooling lines under the car. I'm leaving the sides open for cooling and lining the bottom of these gussets with aluminun sheet (1/8") to keep the majority of debris/crap out and protect from loose road junk damaging them. I'm done now - sorry.

[pktzygt]

^^ What a great way to heat up the fuel.

Pretty obvious they never finished it..

If I were to do that, I'd run braided fuel lines with AN fittings in another area. Also a subaru transwith cable shifter would more than likely free up space.