BTW, after too many years of being to busy to work on my Renesis /
Glass Goose project, it looks like I may be slowing down enough to
restart. Luckily I have been flying (Skymaster) in the interim.
Lots of catching up to do!
You may remember that I have a Bruce Turrentine Renesis 6-port and
Tracy's EC-2 and redrive. I see that the EC-2 only supports 4
injectors, while I have 6 altogether. Do you know if anyone with a
similar configuration simply did not use (blocked off) the two engine
block injector ports (red injectors)? Or it necessary to use all 6
injectors?
You may also recall that I built a small intake with throttle body
based on the original intake manifold, so I don't have the long
runners. I realize this will produce less HP, but I only need about
180-190 -- which might make the center injectors less important? ( I
can also re-do the intake relatively easily if needed.)
Thanks,
Scott Gettings
Perhaps some one will read this and respond. In theory you do not
need them with Tracy's EFI. However tuning with Tracy's is always a
pain in the butt :-)
It is pretty easy to do your own EFI with a Maximite. The easiest
hardware control computer in the world to program.
Not a very steep learning curve. I can help with out a lot of time or
trouble and you would be doing all 1000 people on here a big favour
as it would be open source. You could use all six injectors for
smother running.
Paul Lamar
I will definitely have a lot of catching up to do! So the Maximite
will handle both the EFI and ignition coils? The programming is
beyond me, but my brother might also help. I assume I could test the
Maximite on my RX-8?
I will look for a source unless you have one handy.
Scott Gettings.
CircuitGizmo sells them in the states.
http://circuitgizmos.com/
Version 2 is now out with higher performance.
The web site does not do it justice. Some times I think CG doesn’t
understand just exactly what it does. It is like a complete DOS
computer running QB with a solid state 64Gig hard disk.
"The CGMMSTICK and CGCOLORMAX have the Maximite BASIC (MMBasic)
interpreter programmed into the PIC32 microcontroller. "
Not only is the BASIC interpreter programmed into the PIC32
microcontroller the programming editor and a disk operating system is
also built in to the microcontroller.
The Maxm+doc jpg shows a Maximite set up next to another computer
running the PIC BASIC pdf doc for rapid access to any BASIC command
info. This is a major breakthrough in the ease of programming micro
controllers.
For $57 it is an extreme bargain.
BTW
Harbor Freight sells a low cost one cylinder piston engine. Perfect
for getting your feet wet in EFI.
Once you get that to work expanding the number of injectors is a
piece of cake.
Paul Lamar
To get on step in the water quicker 250HP might be a good idea. The
p-port conversion is inexpensive and makes the manifold easier. Put
two injectors in each intake pipe. For redundancy, set it up to run
one on each with one Maximite and the other two with another. You
could set up the ignition the same way. One for leading and the other
for trailing. Or one to run 1 leading and 2 trailing and the other
for 1 trailing and 2 leading. Better insurance on keeping the power
up.
Dale Davies
Scott has been on here for many years Dale.
Paul Lamar
Thanks for all the great input, everyone! I will order one or two
of the computers.
Do you think I will be able to test its operation on my RX8 if the
sensors are disconnected? I don't know if the oil metering pump
might be affected?
I still have most of the cooling system to do on the plane's Renesis
engine, so it won't be running any time real soon. It would be nice
to test this component separately.
Scott Gettings.
I thought about testing the LI ignition on the RX8. I decided it was
more trouble than it was worth because of all the sensors the stock
system uses. I would have had to cut into the wiring harness.
Much much easier to test a cheap one cylinder engine. I made a
electric starter out of a 1/2 drill motor. I got tired of jerking on
the rope.
Hopefully your RX8 is still running fine.
It would be much easier to do it on the engine in the aircraft rather
than the RX8 as any sensor installation wiring would have to be done
only once.
Paul Lamar
So I assume one can't simply disconnect all the sensors on the car
and use the Maximite instead for a test run. Rats. I don't know
enough about electronic engine controllers to know how to extrapolate
programming from a 1-cylinder engine to a renesis, or how to tweak
the code you previously included. Is there a very "basic" reference
on these methods, and specifications that might help bring me up to
speed? I have some local EFI/Rx8 talent as well, but I was hoping
for something more of a plug-and-play to minimize the complexity of
this part of the project. e.g. Tracy's EC-2.
Anyway, my Rx8 is running fine, but you may remember I had to replace
the engine at about 50,000 miles and 8 years. The original engine
used very little engine oil -- perhaps 1-2 qts between oil changes.
I mentioned this to the dealer, who discounted it as within normal
limits. (I was not using synthetic oil, BTW)
So I was naively assuming this was OK -- until the day the oil usage
abruptly increased to 1 qt every 150-200 miles. The compression was
OK, no visible leaks, and no smoke in the exhaust. Despite being
well out of warranty, Mazda covered 50% of a new engine, which now
uses the normal amount of oil. I asked to buy the bad engine, but
this was declined by Mazda. I'm assuming bad side seals due to poor
lubrication, causing just enough oil burn to not be visible. We may
never know.
Scott Gettings
Well you can but you have to dig into the wiring hardness and for all
practical purposes that will destroy them.
To add injectors:
Each injector has a small chunk of code that looks like this.
Assume the first injector is connected to pin 10 on the computer chip.
Pin(10) = 1 'set pin 10 high to injector on.
for x = 1 to mixture-value-number :next 'delay for the amount of fuel
needed.
Pin(10) = 0 'set pin 10 to zero.
Now all we have to do is add 3 injectors connected to pin 11, 12 and 13.
Pin(11) = 1 'set pin 10 high to injector on.
for x = 1 to mixture-value-number :next 'delay for the amount of fuel
needed.
Pin(11) = 0 'set pin 10 to zero.
Pin(12) = 1 'set pin 10 high to injector on.
for x = 1 to mixture-value-number :next 'delay for the amount of fuel
needed.
Pin(12) = 0 'set pin 10 to zero.
Pin(13) = 1 'set pin 10 high to injector on.
for x = 1 to mixture-value-number :next 'delay for the amount of fuel
needed.
Pin(13) = 0 'set pin 10 to zero.
No more complicated than that.
Computers do everything only one step at a time. It happens so
fast that it looks like it is doing everything at once.
In this case the injector is only on for about 10 thousandths of a second.
squirt squirt squirt.
Paul Lamar
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