Greetings from AR, USA.

[AndreyB]

always good then things start to WORK!

[Sam]

Also a good thing when your effort to build a transmission that handles 600hp like it's nothing pays off. Words do not describe how happy I am about how this turned out. This is the first time I've ever even touched a transmission.

[Sam]

So, do you think rusEFI can handle a 600hp supercharged V8? I'm willing to bet it can. I'm not gonna go with a turbo anymore, probably an Eaton M series blower.

[kb1gtt]

Pressure wise depends on the sensor. I'm assuming mechanical BOV, but if you are thinking of software controlled BOV, it has not been developed. Supers are harder to properly tune, and I'd suggest the toothed belt or direct drive for sure. I don't know of any reasons why rusEFI can't do it, but I could also be missing something. I guess you have to keep an eye on where you put the throttle plate, as the super can over power it if it's put in the wrong spot. Does suck when your super forces you to WOT.

[Sam]

What do you mean by the supercharger overpowering the throttle body? I've never heard of that happening before. I was gonna probably use the ford throttle body packaged with the Eaton supercharger, along with the TPS that goes with that. Either that, or use a 90mm throttle body from China and rig up a TPS to work with that. There's no BOV with these. There IS a bypass valve so boost can be off at idle. I believe there's a relatively simple mechanism to control this. Just a reminder, these are from Shelby GT500s, I think they're twin screw or roots, and can be found on eBay for decent prices. Check out this thread here:
http://ls1tech.com/forums/forced-induction/1462971-cheap-supercharger-kit-part-ii.html

I'm not concerned about sensors really, since I can make any necessary modifications necessary to support the power I'm going to make. I'm only really concerned about the overall tunability of rusEFI. That's it. I'm not concerned about the small bugs I may encounter, or sensor issues. That's just part of the game with new tech like this.

[kb1gtt]

I understand it's common that you have intake air --> super --> air cooler --> butter fly --> engine. We'll call that super A. However it's also common for intake air --> butter fly --> super --> engine. We'll call that super B. I think super B is more common when you bolt super direct to the intake manifold and can't add a cooler or TB between the super and engine. I believe Super A is more popular as you take the time to cool the air that's been heated by compression.

In super A, I understand the BOV is typically very close to the intake manifold, and typically has a signal pressure line connected, such that if you exceed a pressure it dumps the pressure very rapidly to the intake, or to atmosphere. This prevents pressure spikes which lead to detonation and destruction. The waste-gate / bypass valve / control valve, or what ever of it's 100 names we want to call it, is more of an analog signal that can proportionally open to control average the intake manifold pressure. However when you snap the throttle closed, the pressure spikes and the BOV dumps that pressure rather than folding up your butter fly and sucking it into the valves. Think of it like water hammer when you shut your sink faucet closed rapidly.

I understand the BOV and control valve can be electronic controlled, or mechanically controlled. Electronic control can be a bit faster, but requires more development from rusEFI. Mechanical control is very common, so would probably work for what you want to do.

If these are mechanically controlled, then it's really little more than a typical engine setup, and I don't see any real issues. If you are aiming for those valves to be electronic controlled, then it's still do-able, but would require development resources from rusEFI.

[Sam]

There will be no BOV in my setup. I believe the bypass valve is vacuum actuated, but it might have a solenoid to control the vacuum source to it. I believe it's sort of an on/off thing, but I'd have to do some reading. The other things I'm curious about are:

Alternator control
Water pump control (going electric)
AC control
Dual radiator fan control (going electric here)

I can source a separate controller for AC, alternator, and the cooling system if I need to. Just a bit curious about the capabilities here.

[kb1gtt]

AC is usually on off solenoid which can be a switch. The ecu usually cares to know as it's the load increases. Often the idle will increase.

Alternator control has been done via PID control loop. It used a high side MOSFET which not part of Frankenso

Rad control is done via flex IO but it needs the IO to be available aka not use for injectors and such.

Not sure about water control perhaps done with flex IO but I don't know how water control needs to work. Would also need the io available.

[klyttle]

Not sure about water control perhaps done with flex IO but I don't know how water control needs to work. Would also need the io available.

The electrically-operated coolant recirculation systems that I've seen demoed have their own dedicated electronic controller. Not sure (though I doubt) if any are equipped with any sort of communication link (like a CAN interface) for ECUs to know what these separate controllers are up to; something like that would be quite handy.

[Sam]

My AC compressor seems to constantly switch on and off. I think it's so the evaporator won't get too cold and frost over. IMHO I don't really see the point of having the cooling system communicate with the ECU, because it's not like I'd really want the ECU to do anything in particular if I started overheating. A dedicated controller would probably work just fine for my preferences.

[kb1gtt]

Switching on and off compressor on an AC system is usually a sign that the amount of R134A in the system is not correct or that there is a blockage in the system. It commonly means it means it's low on refrigerant, but it could mean it's high, or that you have to much oil in your system, or you have some moisture that's causing a blockage, or that you have some other debris causing a blockage.

You have some pressure safety switches typically called suction and discharge switched and those notice the wrong pressures, which is what turns your compressor on and off. If you are low on refrigerant, your compressor will pull into a vacuum which is not good as it tried to pull in air from outside the system. Running in a vacuum can lead to compressor damage / seizing compressor and it does not generate cooling when it's running in a vacuum. So it's common to have a switch that turns off the compressor. Then eventually the pressure returns, and the compressor turns back on and starts pumping.

Another possibility is that you have to much refrigerant. In that situation the compressor forces to much refrigerant in the high side on the discharge side of the compressor, which then runs the risk of rupture and damage, so the pressure switch turns the compressor off, until eventually the pressure drops. If you have a restriction on the high side you can also get these same kinds of excess pressures. A common reason for a restriction is that there was humidity in the system which is frosting up. Before you charge a system, you are supposed to pull a vacuum on it. I would suggest you pull a the vacuum to damn near 0 psi for 8 hours. This gives water droplets an opportunity to evaporate. However most auto shops won't let it sit on vacuum that long, they pump it down for like 10 to 15 minutes just long enough to get the O2 out of the system. Then they rely on the drier/filter (if it has one) to catch the remaining humidity and debris. However those are often not replaced and are only sized for one use, so that's typically not going to work very well.

Any how, the long story short is that you generally only need to get the signal to the ECU such that the engine can make some adjustments because it knows there is an additional load. Typically that means a slightly increased idle. Typically the AC system is a self contained system. However there are many configurations, some that use a TRO or TXV valve. Those can be electronic controlled, but are reasonably rare in any system, and even less common in automotive systems. So it's possible you have AC control's but probably not.

[Sam]

All I know is, my truck isn't the only one that does it. Seems like all of our cars have compressors that run for 10 seconds, then switch off for like 5 seconds. My truck just has a clutch switch and nothing else.

[abecedarian]

It's quite common for an A/C compressor to cycle- if it doesn't cycle you probably have a problem.

My '81 VW Scirocco did it; my '84 Chrysler Laser Turbo did it under ECU control during moderate to heavy acceleration; the '88 Toyota 4Runner does it; the 2000 F250 I used to drive for work as well as 2004 F150 I drive currently for work do it, both under ECU control.

Most have an amplifier or similar that will interrupt the compressor clutch when the high-side pressure exceeds some value; some also cut out for low pressure.
Some systems are tied to evaporator temperature so that the evap core doesn't get so cold as to permit condensation to freeze on it.
Others also cut out the compressor based on acceleration / engine load so that maximum power from the engine is available when the pedal's to the metal.

Many 'modern' systems with digital climate controls control the compressor via microcontroller with mechanical fail-safes.

[AndreyB]

Trigger shape:

http://www.msextra.com/forums/viewtopic.php?f=101&t=46456&p=333681

[AndreyB]

Is it possible to take 2 of those 12 INJ drivers and use them for ignition, allowing for sequential everything?

it would probably be easier to have a small extra board somewhere - http://rusefi.com/forum/viewtopic.php?f=4&t=450

[AndreyB]

The idea I was thinking of was to communicate information to the arduino via CAN so the arduino can have the information it needs to control various things, effectively expanding functionality. I.e. perhaps have coolant temp fed to the arduino over CAN, and engine load, as well as stuff like RPM and whatever else since I actually plan on having the same arduino control my gauges.

that should not be a problem - your Arduino would act as a CAN gauge from rusEfi perspective

[kb1gtt]

Yes it CAN remote things. There are many options for many things. Most of those things need to be less timing critical.

The 6 hi/lo drivers will drive fairly strong to + and common voltage levels. Using a pull up resistor (weak drive) with a low side drive (strong drive) tends to warp the signal as it's not being driving hard to that high side. While it might be physically possible to use two INJ low sides for IGN, I would expect it to be problematic as there would be 2 different driver technologies with different signal delay characteristics. I would suggest an add-on board that adds 2X extra channels rather than re-purposing low side channels.

[AndreyB]

Do you have any soldering skills? I can probably assemble the most challenging sections of the board for you but not the whole board.