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Previous Next Up Topic Engines / Subbug - Subaru Power / Deserter GS radiator install (15450 hits)
By @Jeff GS Date 2007-11-21 13:38
I though I'd start a new thread covering my Deserter GS radiator installation.  While I'm still working out the details of the installation, I've made some decisions on how I'll proceed:
1) I'm going to use a dual pass radiator, with inlet and outlet on the same side of the radiator. 
2) I'm going to follow the Renegade Hybrids cooling hose guidelines of using 1" ID return line from engine to radiator and 1.25" ID supply line from Radiator to engine.
3) Since my Subaru turbo motor uses 1.5" hose connections, some adaptation and hose size reduction will be required between engine and radiator.  Right now the plan is to utilize short silicone reducer hoses to make the transition, right off the engine hose connections.
4) Radiator will be custom, probably a Griffin, with 1" return and 1.25" supply nipples, no filler opening, upper and lower 1/4NPT bleed/drain connections, mounting bosses for a fan shroud and a 3/8NPT temperature sensor fitting.
5) I think I'm just going to use a single 13" fan, centered on the radiator.  Spal makes one that flows over 1700CFM that should work well.  Not sure about running a shroud at this point?
6) Overall radiator size I'd like to use is 13" tall x 24" wide, with dual 1" tubes, all aluminum construction.  This is 2" wider than the "standard" Scirocco type radiator, but otherwise will be very similar.

With the above parameters in mind,  I've now gotten the front framework in place enough to begin scoping out hose routing and clearance issues.  Unfortunately, it seem like however I position my "mock" radiator the hose nipples want to wind up running directly into a frame or suspension member!  At least for straight out of the end tank nipples.  I think I'm going to have to get creative with the hose connection angles and hose routing.

I was hoping to just run an off the shelf radiator, and the closest I've found is the AFCO 80107N.  It looks near ideal if you could use the standard hose outlet locations.  But that's not the case on my very customized chassis.  I've read other folks have had an easy time working with Griffin for custom radiator builds, so I'll be calling them when I get ready to have it made.

I'll provide updates as this comes together.  Right now it's looking like I'll be finalizing the radiator design and details later in the Spring.

By Terry F Date 2007-11-21 22:34 Edited 2007-11-21 22:43
Just a thought Jeff, it's possible to incorporate a "port" into your frame so the radiator hose(s) could pass though without the restricting sharp bends, IF you can avoid the suspension arms...

By @Jeff GS Date 2007-11-22 13:27 Edited 2007-11-22 13:32
I thought about "through the frame" plumbing Terry, but really didn't build the frame with that in mind.  One thing I didn't want was lengths of the frame running either in or next to the cockpit at 180-200F!  I guess you could try and insulate, but think this is something you'd have to design in from the beginning.  Some race cars used this.

I'm undecided whether I'll use hard plumbing (aluminum tubing) or just run Gates green-strip hose from front to rear.  Either way I'll be wrapping the tubing or hoses with pipe insulation since they'll mostly be inside the side pod.  Ideally I want to minimize connections as those will be the weak points in the system.

Another hang up is at the water pump connection.  My engine has the inlet facing towards the left/drivers side  (as mounted in the car), but the radiator inlet/outlet will be on the right (or left depending on how I have it made).  One of the hoses has got to cross over from one side of the car to the other, since the upper engine outlet connection points towards the passenger side.  I'm hesitant to run the hoses down the driver side, as there's a lot of brake/clutch stuff on that side up front (already crowded!).  If I run down the passenger side the lower hose will have to cross over at the rear and do a 180 to get back into the water pump inlet.  Hopefuly this dilemma will calirify itself once I get more hardware in place.  I've also got oil line plumbing, filter and cooler coming off the passenger side of the engine that has to go somewhere!
By Paul Moran (DBA Architect) Date 2007-11-30 16:22
Jeff - Do you have any diagrams of your proposed layout?

I wonder why Griffin couldn't flip the radiator ports to make your hose running easier.  I would think there has to be some combination that would allow the tubes not to cross, but knowing you, you've gone through all the possibilities.

I've been very happy with my Griffin radiator - looks like new still.  I think it may be too big now that I have seen what Subaru puts in their cars. My set up with the fan running constant (yes - computer isn't turning the fan on properly so I hard wired it for now), it takes about 15-20 minutes even at highway speeds to get to 180 degrees F. 

Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By @Jeff GS Date 2007-12-01 20:10
No diagrams so far Paul, unless you count the "napkin design sketches"!
I've asked the guys that do Subaru 914 conversions how they make the transition at the water pump, since these generally run the water hoses underneath and near the middle of the car, front to rear.  As mentioned above, the hoses already have to make a size transition from 1.5" at the W/P inlet and upper hose outlet down to 1.25 lower, 1" upper.  The upper hose is easy - since it's pointing ~ towards the right front coming off the motor.  Easy enough to just run a silicone hose transition and then into the 1" hose going forward, following the chassis just outside of the side braces.  This hose will stay more or less level (or slight elevation?) going forward, and into the radiator inlet.

The bottom is the most problem, though if I were running that hose down the driver side it would be more straightforward, mostly just needing a 90* transition out of the pump/thermostat inlet to run it forward.  I'd prefer to not have a lot of curves to negotiate going into the W/P, since it wou8ld seem to need good unobstructive flow to avoid cavitation.  One of the 914 guys responded and said he's using the stock WRX lower hose, shortened a little at the forward end.  I may have to pick up one of these hoses just to see what it looks like and applicability.

Still, one hose or the other has to cross over to the other side of the car.  Having Griffin make the radiator with hose fittings on the left or right is no problem - they already offer their Scirocco models with this option.

The small upper hose would appear easier to make cross over somewhere, just because of the smaller size.  OTOH, ther may be more room towards the bottom of the radiator to run the lower hose from passenger over to drivers side, running along the bottom of/behind the radiator?  That way the lower hose could run down the driver side of the car and basically straight back into the "side feed" thermostat inlet.  It just has to clear the fan near the bottom at the radiator.

All this "imagineering" is fun, but I'll really have to get the engine and front suspension in place to reall see how it should go together.
By Sandsurfer Date 2007-12-02 00:23
I would try to use as much aluminum hard line as possible. The aluminum will aid in cooling, much more then the rubber hose. It sounds like a great project.
By @Jeff GS Date 2007-12-02 19:11
It would Jerry, except most of the lines on my Deserter will be buried in the side pods!  Still considering using aluminum hard lines though - but seems there is some trade-off.  Expense and hassle of getting the tubing, getting it bent properly, then adequately beading the tube ends.  If I already had the tools I'd likely go that way - but a new die for my tube bending will run over $100 (for the 1.25"), and I'd have to get another $75 or so in beading tools.  The rubber hose doesn't require all that, just slip on the connectors and tighten 'er down!

However, wherever tight bends are necessary, it would be advantageous to run properly bent hard lines.  Keeping that option on the table.......

By @Jeff GS Date 2008-01-22 01:12 Edited 2008-01-22 01:20
A small but important update to my cooling thread.  One of my goals for the MLK holiday weekend was to try fabbing up a cooling hose adapter/coupler to change hose sizes between the water pump and the radiator hose running up to the front of the car.  I figured the cleanest approach would be to run an angled hose off the water pump/thermostat inlet (which would be 1.5" ID to fit the thermostat nipple & possiby using a portion of the OEM lower hose) and connect it directly to the 1.25" hose running up to the radiator with a "stepped" adapter.
Many hours spen on my mini-lathe and Ta-Da!

Other end:

Note that the ID is tapered on the larger end to smoothly open up to the larger 1.5" diameter hose.  Came out better than I expected and fits the bill perfectly!

Another small step out of the way......
By Mel Adjusted Date 2008-01-23 06:38
Jeff, A little trick I learned years ago was to use nickle plated sink drain pipe (1 1/2") in my radiator lines and only use the rubber hose for the bends. If done right it looks real good and neat. You can buy the pipe real cheap and get it in all different shapes.
At my age.. Everything I buy comes with a lifetime guarantee..
By @Jeff GS Date 2008-01-23 12:45
Mel - good idea and one I may think about incorporating.  How do you bead the ends of the tubing so the hoses won't come off?

That's one of my biggest "hitches" in doing the custom hard tube work for the cooling system.  I'd like to use aluminum tubing for the long side runs, but getting the ends beaded is a bit of a problem.  I've got a home-made beading tool on the back burner - the first iteration didn't work properly.  I may get it back out this Winter and see if I can do some modifications and get it functional.
By Paul Moran (DBA Architect) Date 2008-02-20 23:43
I'm also in search of a beading tool (glad I know the right name for it) for 5/16" (fuel lines), 1/2" (heater hose) and ideally the larger 1 1/2 or 1/4 for the radiator tubes.  Please keep us posted (I'll do the same) if you find a good source for them.

Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By @Jeff GS Date 2008-02-21 01:04
Here you go Paul:

These are the least expensive beading tools I've come across.  Unfortunately, they're meant only for aluminum tubing (no steel) - but I talked to someone on STF that had and used a set of these and said they work great.

If you want more elaborate you have to step up to the pro aircraft type beading tools - much more $$$!

By Paul Moran (DBA Architect) Date 2008-02-21 03:56
Those don't seem like bad prices and I'm just working with aluminum.  Only problem is they don't have a 5/16 size one...  I'll have to get the 1/2" one shortly along with some 1/2" tubing.

Chicago, IL
EMPI Imp 1002 ('69)/Subaru EJ20 Turbo/LinkPlus ECU
By @Jeff GS Date 2008-02-21 21:35
Shop around Paul - they're a standard Earls product.  Might be able to find a better price?

Previous Next Up Topic Engines / Subbug - Subaru Power / Deserter GS radiator install (15450 hits)

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