Here is a bit of eye candy to satisfy all of you. I will try to annotate the pics as I go. Some of it looks rough, but this was a prototype/fab as you go project and I used quite a bit of scrap material that I had laying around. You don't want to know how much time I have in it... ah the joys of being a trailblazer.
And now, on with the show....
Fans with split loom and clamps on wiring and lower shroud/support. The rubber flaps cover holes that allow air flow at highway speed. The fans suck flaps closed to get better pressure drop across rad at low speed with fans on.
Fans with lower shroud/support. Here you can see the holes. There is two layers of topper tape between the molded fan shroud and the aluminum one. The 3 legs on the bottom of the lower support go into 3 holes in the factory lower shroud support on the van as you will see later. Also note topper tape at edges on lower shroud to protect from rubbing on rad core headers. I also split some 5/32" vacuum hose and glued to the outer upright portions of the molded fan shroud. This helps seal the shroud against the radiator, protects the rad core headers from rubbing, and makes it just enough more difficult to install the fans to make it fun
Upper rad/fan support. Mounts to body using 3 factory holes.
I incorporated the factory long U shaped rad support bushings. I didn't use the ones from the '02 as they are quite a bit taller. I pulled these from an earlier ('80s-early 90s) astro at the junk yard when getting parts for a Transport. I also added one more rad support bushing on each side that I modified from grommets. These go over the ears that stick up from the side tanks. There is a single layer of topper tape on the underside of the upper support where the fans bolt on.
Here you can see a 1 1/4" square piece of foam that is placed in the channel across the top of the rad to seal against the upper support. You can also see the factory lower shroud support. This piece also supports the tubing loop that is used as a power steering fluid cooler. I added two or three more screws in line with the existing ones that attach it to the body being careful not to screw into the wire harness that lays on top of this area. There are 3 slots where the factory lower shroud snaps into this piece. These slots are where the legs on my aluminum lower shroud/support slide down in. This makes it easy to lift the whole assembly up and out once the upper support is removed. On the far right you can see the connectors for the passenger side fan.
Placing the temp probes took some thinking. The instructions say to carefully separate the fins enough to insert the probes and do not have them protrude through the core. No mater how careful you are they were not tight enough for my liking with 4000cfm of fan sucking on them. My solution was to place a grommet on them on both sides of the core tightened with a zip tie. This makes them protrude through the core but they are inside the grommet. I also placed them up high in the top or second row so that they are actually behind the sheet metal of the body and do not have any airflow past them. On the wires you can see a grommet that fits into a notch in the fan housing. This allows the fans to be removed without needing to remove the temp probes.
Look Ma... no fan, but a nice new belt!
To keep from being pinched between the new fans and the brake master cylinder reservoir, the upper rad hose needs to be flipped end for end. It just touches the rubber cover over the steering shaft and the pressure hose going to the brake booster. The hose does "kink" just a tiny bit at two of the bends up by the thermostat housing. This should not be a problem and has not yet proven to be a problem as it is ever so slight, most home wrenchers and sadly even quite a few techs probably wouldn't even notice. Note the upper hose is the pressure hose, the lower is the suction this should also prevent this from being an issue.
The upper hose now runs just over top of the idler pulley and no longer has the upper fan shroud to hold it up. I fabbed a piece of aluminum that bolts on with the A/C compressor strut. The hose should have plenty of clearance and it shouldn't flex enough, even when hot to contact the pulley, but.... It doesn't really act as a support, more of an insurance policy. I am actually more concerned with the belt being thrown, or throwing something than I am with the hose bending down and touching the pulley.
The fans and lower shroud installed.
Upper shroud installed.
There is about 1/4" - 3/8" clearance between the brake master cylinder reservoir and the fans. There is about the same clearance between the fans and the top inboard bolt on the front of the steering gear box. Boy did I get lucky. This shouldn't be a problem as all of these are mounted to the body or subframe and if they move that far you probably have more serious problems. This does make for a tight fit getting the fans in and out but it is easy once you know the right angle, and in my opinion far easier than getting out that !@#$!@%#$ factory top shroud.
I replaced one of the bolts that attaches the drivers headlamp bracket with a longer one and used this as a mounting point for my little black box.
I added a washer on the bolt as the weld nut is not real big.
Say hello to my little black box...
Two fan controllers, 3 relays, and a bit of wire is all that fits. The box is just the right size. I used double sided tape to hold down the controllers and relays and prevent too much vibrating. It really looks confusing from this pic, but it isn't too bad really. I have things wired in such a way that by carrying a spare relay (I had an extra that came with the fans and controllers) and a couple of jumper wires with the right spade terminals on the ends I can easily bypass any one of the components, or multiple ones in the event of a failure.
My little black box nestled away in the corner. I used a brass replacement post for the positive battery cable that allowed me to have a good power source for my fans. On the far right you can see the factory ground cable from the battery where it attaches to the body. The bolt attaching it has an 8mm threaded portion protruding out just wanting more ground cables to be added here so after a nut and a couple of serrated lock washers I was happy to oblige. As you can see I don't like wires all over the place... maybe I should buy some stock in a split loom company [-X
The UBEC (underhood bussed electrical center)! Here I used mini fuse taps to tap a circuit for my key on signal. I tapped a circuit that is on in Run and Start only, not accy. This is important on the newer vans due to the RAP (retained accessory power). I also found this the easiest place to tap for the A/C compressor clutch signal. I used another fuse tap on the diode for the compressor clutch. You must tap the positive side of the diode not the ground side. To make it more confusing this diode is in backwards to allow current from the voltage spike to flow from the ground side back to the positive side of the compressor clutch coil. Also you need to make sure you put the diode back in in the correct direction or the voltage spike from the clutch turning off can do nasty things... that is what the diode is there for. People don't like buying new PCM's and IP's. I had to trim the fuse taps just slightly as the surface of the UBEC is oddly shaped where the fuses insert.
The cover for the UBEC had to be trimmed to allow my split loom to pass through.
You didn't forget about mounting the airbox now did you? Details, details... I used two pieces of heavy strapping complements of Tru-Cool. I bent them to shape and used 2 long bolts to protrude up into the airbox.
Installed fender washers and locking wing nuts on bolts. (nylock)
All buttoned up!
Still have yet to try towing. I wired the fans with two controllers, one for high speed and one for low, and used a third relay to put the fans in series or parallel, as GM does on all stock dual fans. The high speed didn't kick in once last night. The fans are loud on high, almost sound like a siren, but man do they move air. I should now have cooling better than stock LS1 vettes and f-bodies. Their rad is same size except 23 5/8" wide instead of 28 1/4" and also has a 1" core, and I have read that the stock fans are somewhere between 3500 and 3800 CFM. I will try to post pics in the next few days. I fabbed the upper mount and the lower shroud extension out of aluminum. If anyone is interested I could make more of these, or even a kit. The fans are only $200 at summit and the controllers are $40 ea. At $3 gas prices the whole thing should pay for itself within 2 yrs. with just a 1mpg gain and I think I will get more than that.
