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RobertSmalls · 08-13-2010, 09:42 PM

I'm really not driving much lately, so the boat tail frame is still hanging up in the garage, waiting for me to attach a skin and some lamps to it.

I've assembled a MIMA controller, shown here almost completed:

It was $125 for these seven PCBs and the preprogrammed 40-pin microcontroller. It was another $125 or so for the components to populate the boards. This was no harder than assembling a MIMA-L despite having ten times as many components, because the traces are already laid down for you here.

I now have four toggle switches to the left of the steering wheel. From left to right, the switches turn on and off the fuel injectors, clutch switch assist/regen disable (somewhat redundant now that I have MIMA), DC/DC converter, and MIMA.

I've only put about 10 miles on the car since installing MIMA. Initial impressions are positive, but not overwhelmingly so. The car cuts out assist after a few seconds, and MIMA hasn't changed that. Perhaps my MIMA controller is slightly broken, maybe it was related to the state of charge recalibration I just had, maybe I've been too lead-footed... I'll figure it out eventually. Meanwhile, EV mode is limited to a few seconds out of every minute.

Other things I want to use MIMA for:

*faster regen braking. It works! The default setup gives you a full 50A until RPMs fall too low, then tapers it off so the car slows down smoothly. Call in full regen with the MIMA stick, and you get 50A down to... well, low enough RPM for DFCO to end, and the engine to fire angrily. Much faster stopping, and the guy behind me is happier.

*holding lean burn while accelerating. I expect MIMA to provide big payback here, but I haven't gotten the engine hot enough to test it yet.

*disabling Honda's undocumented automatic background charging. There's an option for that somewhere in the controller, I just have to find it.

*cruising faster than LB would allow, then dropping to stoich to recharge every 10-30min.

The Insight is known for developing rust on the seats' steel rails, where it's bolted to the Al floorpan. That rust is the benign half of the galvanic corrosion equation. I pulled both my seats, hit the rust with a wire brush and rust converter, then applied black rust resistant enamel. I don't think there's much I can do about that corroded frame member, though.

I also noticed moisture under the carpet, and I'm not sure that can be helped either.

08-13-2010, 09:42 PM	#178 (permalink)
RobertSmalls Left Lane Ecodriver Join Date: Aug 2008 Location: Buffalo, NY, USA Posts: 2,257 Prius C - '12 Toyota Prius C Thanks: 79 Thanked 287 Times in 200 Posts	I'm really not driving much lately, so the boat tail frame is still hanging up in the garage, waiting for me to attach a skin and some lamps to it. I've assembled a MIMA controller, shown here almost completed: It was $125 for these seven PCBs and the preprogrammed 40-pin microcontroller. It was another $125 or so for the components to populate the boards. This was no harder than assembling a MIMA-L despite having ten times as many components, because the traces are already laid down for you here. I now have four toggle switches to the left of the steering wheel. From left to right, the switches turn on and off the fuel injectors, clutch switch assist/regen disable (somewhat redundant now that I have MIMA), DC/DC converter, and MIMA. I've only put about 10 miles on the car since installing MIMA. Initial impressions are positive, but not overwhelmingly so. The car cuts out assist after a few seconds, and MIMA hasn't changed that. Perhaps my MIMA controller is slightly broken, maybe it was related to the state of charge recalibration I just had, maybe I've been too lead-footed... I'll figure it out eventually. Meanwhile, EV mode is limited to a few seconds out of every minute. Other things I want to use MIMA for: faster regen braking. It works! The default setup gives you a full 50A until RPMs fall too low, then tapers it off so the car slows down smoothly. Call in full regen with the MIMA stick, and you get 50A down to... well, low enough RPM for DFCO to end, and the engine to fire angrily. Much faster stopping, and the guy behind me is happier. holding lean burn while accelerating. I expect MIMA to provide big payback here, but I haven't gotten the engine hot enough to test it yet. disabling Honda's undocumented automatic background charging. There's an option for that somewhere in the controller, I just have to find it. cruising faster than LB would allow, then dropping to stoich to recharge every 10-30min. The Insight is known for developing rust on the seats' steel rails, where it's bolted to the Al floorpan. That rust is the benign half of the galvanic corrosion equation. I pulled both my seats, hit the rust with a wire brush and rust converter, then applied black rust resistant enamel. I don't think there's much I can do about that corroded frame member, though. I also noticed moisture under the carpet, and I'm not sure that can be helped either.