Hey MasterChief, I hope I can help you out and give you something you’re looking for. Really would like to come in at that price point too, we’ll see how it shapes up as time goes on (hopefully sooner than later).
I'm updating this thread with a bit of test results and feature tweaking heads up. Nothing too much new, other things have consumed my last few weekends and my week days have been rather busy. My firmware friend has been too busy with his business and family to get a crack at the RC2 release, but said he’s looking to free up shortly, which is understandable, it’s a side project.
I did manage to get 2 low ohm coils to run a current profile on and one higher ohm Dyna (2.2 ohm). One of the low sub 1 ohm coils is common GM C849 by Wells Manufacturing Corp. that Doug suggested. The other sub 1 ohm coil was a Ford Motorcraft DG508 coil on plug; the same COP that 23tbucket tried on his EFI bike and seems to fit real well with the available room on the CB. Both of these coils are readily available, inexpensive, and should provide a decent look at what charge time (dwell) will satisfy them.
I used a different Oscope and the actual ignition instead of a test circuit with the same IGBT, so I ran all the coils over again. The coils are being fired with the ignition loaded with the stock 190/170 charge/discharge firmware, this is to allow the higher ohm coils enough time to fully saturate. I loaded the RC1 8.2mS dwell firmware for the quick charging sub 1 ohm coil so as to not heat the electronic up too much, though testing at a higher RPM would have work similar I suppose.
Below are the results, very much similar to the screen captures posted earlier. The equivalent current per division is around 1.33 amps/division based on the gain of the current measuring circuit.
Dyna 5 ohm
Stock Coil ~4.5 ohm
Dyna 3 ohm
Dyna 2.2 ohm
Ford DG508
GM C849
GM C849 at 250uS/div, this shows the charge ramp much better.
Both the GM and the Ford coils fully charge by around 1.4-1.5mS and draw around 6 amps. I was kinda surprised by the sharp knee where the sub 1 ohms saturate; much sharper than the lazy rounded bend on the higher ohm coils. My hardware friend wanted to see the circuit to verify that the IGBTs weren't saturating, the ramp does look very much similar to the other coil ramp screen captures on the web; thinking there is nothing misleading.
What I would like to do is get a modified version of firmware with a dwell that is fixed at 1.5mS instead of the 8.2mS and do some average current measurements and map it like other 190/170 and 8.2mS current vs. RPM charts. This should give an idea of what they would be consuming real world through out the RPM range.
The Dyna 2.2, these guys started to raise the temp on board quite a bit; I shot 202F at it’s normalized temp in still air with a infrared thermometer with around 78F ambient. Granted it was with the stock 190/170 at 1k RPM (worst case), but a looking into the heat sinking maybe need (i.e. AL lid coupled to the current drivers). This is something that will be looked into when hitting up the heat chamber.
How I can see the iggy shaping up is to add a 4 position DIP switch on the board, there should be enough room on the micro to accommodate it (I/O wise), though the switches will need to move a bit. With this the following functionality could be tentatively added (barring no issues that come up with the firmware side):
o Dip#1 – Vacuum or boost switch installed / No VOES/Boost switch installed. This just moves the external wire that needs to be grounded to enable the timing retard/advance option onto the DIP switch instead of grounding out a wire (convenience).
o Dip#2 – 2 coils / 4 coils. Lets the micro know there are 2 or 4 coils installed and that an add on board is installed that provides 2 extra coil drivers for a COP or individual plug setup.
o Dip#3 – High ohm coils / low ohm coils. Choose weather you would like a 1.45mS dwell or a 8.2mS dwell depending on what type of coils you are using (i.e. stock or high ohm Dyna vs a sub 1 ohm automotive coil). Note, those dwell times are not yet set in stone but are close and cover a reasonably large range of coils.
o Dip#4 – Third rotary switch function select: adjustable RPM window switch (shift light ect..) / Adjustable dwell control. If a dwell control different than the two default choices of 1.45ms or 8.2mS are desired you can choose from 16 different preset coil charge times that should cover a wide array of coils, but you would have to sacrifice the RPM window switch (and vice versa). Choosing dwell control would inactivate DIP#3.
I think these choices would add a decent amount of flexibility and choice while keeping the cost relatively the same. I talked with my firmware friend and he noted that there wasn’t anything he could think of preventing those features to be added. We’ll have to wait and see it implemented to see for sure, but its looking doable.
(sorry for the wall of text)