My wiring harness is off to Jeff Robenolt in Wisconsin to be worked over and turned into a harness adapted for use in a Bus. Jeff is a good egg: a real thinker about ways to improve the art, not just crank out monkey copies of what has gone before. In my case, I'm specifying certain modifications that would have gotten me turned down (or laughed off) by some of the other folks who do the conversions.
The most significant modification is for the circuit and their fans. This isn't actually to make it more exotic or specialized, it is to more effectively use the programmatic intelligence of the Subaru ECU to manage cooling a relatively exotic and specialized cooling environment:
The Scirocco fans are dual power, that way cooling could be increased without adding an additional fan. There are two circuits to drive the same fan: a 250W and a 150W. Put on the AC, and the 150W comes on constant because the AC condenser is sandwiched in with the radiator. AC needs a lot more air volume passing over it (and a guarantee of air volume, when slowed or stopped) to ensure that the AC system will work correctly.
The 250W circuit is to pull air through faster if the coolant got to hot. It pulls a steep 20 Amps at 12 volts. This is not a circuit you want closed all of the time: this is for when you're in the bad spot of Dallas asphalt in August at 110°F in the shade, and you're stuck crawling along, stop and go at 5mph in first gear. The pitch of the blades is so steep, its clear that this fan is designed to come on, waste no time pulling your coolant temperature down out of the danger zone and then shut off again. It shouldn't ever be running all of the time.
The Subaru also has two circuits for fan control, but it is for two different fans. In this case, I'm getting Jeff's help to rework the circuit so that the FAN1 signal from the ECU closes the relay for the 250W pair (40A total draw!) and the FAN2 signal closes the relay for the 150W pair (20A total draw.) The fans themselves will be tapped directly off the battery, for the shortest power path.
Here's the interesting question that Jeff is going to be working on: Does Fan2 only come on in a Subaru application when there is air conditioning? Does the ECU ever trigger BOTH fans even without the AC circuit being closed? I don't know. HE doesn't know. So we're going to find out, and what we learn will help guide the continuing evolution of the VolksarU design.
Those of you who pay attention to power draw may note that, if it were even possible for both fan circuits to be engaged at the same time it would constitute a load of 60A just to run the fans. (Are these fans designed to run at an additive wattage? I dunno. That's what we're testing.) The Alternator on the EJ22 is only designed to put out 75A, which is more than enough to push a 5 passenger car with power-everything down the road. I'm actually hoping that the 150W circuit is AC only. But we won't know until the test is complete.
The second piece of happy news may be documented in a somewhat blurry picture, but it is a beautiful sight to me:
This is the EJ22e engine rotated 180° (upside down) and the beautiful Rocky Mountain Westy engine carrier bar bolted on to the engine with new vibration dampners. On the left you can see that I've mocked up the extension arm that reaches to the rear and bolts to the factory carrier bar chassis holes for the 1972-1973 Type4 based bodies. This is the only design I've seen that does this, and it's brilliant: It locks the carrier into place in three degrees of rotation, and does so without requiring any cutting or welding on the body, re-using as many stock mounting points as possible. In it's own way, it is the perfect demonstration of the VolksarU ideal: Installation is DIY friendly, no body mods needed and is compatible with two decades worth of Subaru EJ series engines. If you decide to trade up to an EJ33 or a Subaru H6 engine...they just fit. A lot of smart engineering, jig and fab work went into this carrier.
To my knowledge, only two other companies offer carrier bars "cash and carry" rather than a custom fabrication each time, but they're both in the UK. (RJES & Fellows Speed Shop.) Both are good products and have the merit of being weld-in compatible with many different models, but require someone to do the welding, so they aren't as DIY friendly (unless you already weld.)
With that, I'm closing up shop and going on vacation. See you in mid-July!
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