28 Sept 2014

A bumpy week, car-wise.

The water/meth controller was returned as “no problem found.” Of course it still didn’t work so I had to figure it out or drop it in the trash. I specifically asked the AEM tech on the phone if the self-test function would work with ONLY 12V connected – yes. The real answer turned out to be No.

The controller requires a direct connection straight to the car battery, the reason not explained. It turns out that this connection powers only the pump and not the controller, which of course isn’t explained either. Through trial and error I found that to power up the controller, the so-called “Enable” line must be set high. In electrical engineering, the term “enable” describes a very low power input which enables a circuit but doesn’t power it directly. What AEM doesn’t document is that their “enable” pin is actually the power pin for the controller, requiring far more power than any enable pin.

With that figured out, the circuit has to be redesigned since I took their word for what “enable” means – to the rest of the world. Worst case a relay will have to be added since the ECU was attempting to drive this “enable pin” with a signal appropriate for the task, but is incapable of powering the unit directly. Minus one point to AEM for mislabeling and misleading people on the meaning of this pin.

In other news:

– With ignition timing now corrected, boost could be increased up to about 16 psi without knocking, but I know I’m pushing my luck. The water/meth will help that situation as soon as the above is resolved.

– When I disassembled the intake to mount the water/meth injectors, a very thin film of oil was found throughout the intake tract – even into the wastegates. This was very disappointing because it means that the nearly-new turbo has an oil leak (which also effectively drives down fuel octane). If this happened to someone else I’d tell them to check that they have the appropriate oil restrictor in place, and a well-routed oil drain-back line. The thing is, the same parts from the previous turbo were transferred over to this one, so neither the restrictor (0.040″) or the drain-back is any different. Sigh… well, it is what it is, so out it came. It’s already boxed up and ready to go. Being only 3 months old I don’t expect major issues getting it repaired or exchanged but that’ll be dealt with tomorrow.

– With the turbo removed, the wastegates were also removed and 5 psi springs installed; with boost control there’s no reason to have high spring pressure. It allows using boost-by-gear which is sort of a poor-man’s traction control, but obviously that’s for later.

– With the turbo on its way out the door, that pretty much answers the question: Midlana’s not going to the runoffs in two weeks. Even if the turbo retailer sends a replacement within a week, I don’t like rushing major engine alterations. Along the same lines, my brother is having issues with the charging system in his LS-3 Stalker. In the name of science he disassembled the alternator to see why it worked for about an hour and then didn’t, finding that a piece of rock-hard insulation broke free and got jammed in the armature, effectively turning into a fly cutter and slicing a number of stater wires. This was the second alternator; the first one was dead out of the box. For the same reasons he’s decided to not drive his car to the runoffs either. Shrug, oh well, we’ll share the gas expense and talk on the way up and back.

21 Sept 2014

About time for an update.

First the good news: My brother’s LS3 engine swap is running and he is starting shakedown drives ahead of our road trip. Meanwhile, I continued work on the water/methanol system installation and it’s now complete and ready for tuning…

The other sort-of good news is that I don’t need the water/meth system for our trip – it appears the brand new controller is dead. Realizing the chances of that are slim compared to me miswiring it, everything was checked out. It doesn’t help that the unit has no power indicator, no indication whatsoever that it’s working or even on standby. Besides how it’s supposed to work (pump starts when boost hits X psi), there’s a Test button to check functionality… which does exactly nothing. The following was checked:

1. The pump works fine wired directly to 12V.
2. The cable running from the pump to the controller is good and runs to the correct pins.
3. 12V is wired to the controller on the correct pins.
4. The fuse is good.

Thinking that maybe the Test switch was defective, the boost, throttle, and rpm trip points were adjusted to zero in order to trigger the pump with the car at rest – again, nothing. Looks like AEM Support will be getting a phone call tomorrow. I’ll admit that the thought ran through my head, “I wonder if this would happen with an Aquamist system.” Sigh… Even if AEM fires off a new one immediately, it’s up in the air whether it’ll be fully functional for the trip, but it won’t hold things up either.

1 Sept 2014

Fabrication of the water/methanol tank is progressing. It’s going between the front rocker arms and typical for me, it’s a bit over the top. It’s a complete subassembly, baffled tank, sump, filter, and pump. The pump is a beast and is larger than my fuel pump, not surprising given that it’s 200 psi! Haven’t decided where to put the controller and gauge. I don’t want it on the dash but it has to go somewhere since it monitors and logs actual fluid flow to the injectors. Neither the control box nor gauge are water resistant so that makes things more interesting.

In other news, my brother finally has the exhaust done on his LS-3 powered Stalker, so hopefully he’ll have it running in time so we can drive the cars to Laguna Seca for the SCCA runoffs. The big event will be whether it starts right up – or not.