Flex Fuel with MegaSquirt Controller
07-01-2008, 01:01 PM
#1
Junior Member
Thread Starter
iTrader: (1)
Join Date: Jul 2006
Location: Colorado
Posts: 402
Total Cats: 2
Flex Fuel with MegaSquirt Controller
The write up in the MegaManual says
http://www.megamanual.com/flexfuel.htm
Does this work with MS-1 as well? I am contemplating switching to MS but need to decide between MS-1 and MS-II.
The main driver for me is to run more timing with the improved octane of e-85, but it's not always available ( and not always 85% ethanol either ).
The writeup addresses fueling adjustment, I assume I will have to add a MS Knocksense to back the timing down if the percentage of e-85 in the tank falls to low and I start to get some knock.
Anyway to use map switching to change the spark map if the concentration of e-85 drops below a certain point?
Is anyone using the flex fuel sensor? How is it working for you? What are you doing about timing?
This is not a "Green" or fuel efficiency exercise, it's all about power.
Thanks in advance,
--Chris
MegaSquirt-II (including MicroSquirt) is the first aftermarket EFI controller with direct flex-fuel support for experimental only testing of ethanol fuels and blends.
Does this work with MS-1 as well? I am contemplating switching to MS but need to decide between MS-1 and MS-II.
The main driver for me is to run more timing with the improved octane of e-85, but it's not always available ( and not always 85% ethanol either ).
The writeup addresses fueling adjustment, I assume I will have to add a MS Knocksense to back the timing down if the percentage of e-85 in the tank falls to low and I start to get some knock.
Anyway to use map switching to change the spark map if the concentration of e-85 drops below a certain point?
Is anyone using the flex fuel sensor? How is it working for you? What are you doing about timing?
This is not a "Green" or fuel efficiency exercise, it's all about power.
Thanks in advance,
--Chris
Reply
0
0
07-01-2008, 03:28 PM
#3
Supporting Vendor
Join Date: Sep 2006
Posts: 2,332
Total Cats: 67
MS-I does not support flex fuel sensors. MS-II can make both fuel and timing changes in response to a flex fuel sensor with the right mods, but it adds a certain amount of spark advance for every % change.
Reply
0
0
07-01-2008, 03:41 PM
#4
Junior Member
Thread Starter
iTrader: (1)
Join Date: Jul 2006
Location: Colorado
Posts: 402
Total Cats: 2
Would map switching based on a value coming out of the flex fuel sensor work?
If not, does the KnockSense provide enough protection?
Reply
0
0
07-07-2008, 07:54 AM
#6
Elite Member
iTrader: (3)
Join Date: Apr 2008
Location: Outside Portland Maine
Posts: 2,023
Total Cats: 19
We have successfully used megasquirt to convert a yamaha snowmobile to flex-fuel. I won't pretend I know all the details as my task on the team was a completely different aspect of the project, but I know we used a flex fuel sensor from a GM vehicle and it automatically adjusts something important depending on the percentage of ethanol in the tank.
I think they (the engine control part of the team) had to generate a gasoline table, and an E85 table, and the megasquirt interpolates between the two tables. That is the part I'm a little fuzzy on though.
I think they (the engine control part of the team) had to generate a gasoline table, and an E85 table, and the megasquirt interpolates between the two tables. That is the part I'm a little fuzzy on though.
Reply
0
0
07-15-2008, 08:34 AM
#9
Junior Member
Thread Starter
iTrader: (1)
Join Date: Jul 2006
Location: Colorado
Posts: 402
Total Cats: 2
(* Hey Matt, did I have the cap on straight in the interview?
)
Reply
0
0
07-15-2008, 12:35 PM
#10
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,020
Total Cats: 6,588
It's on the bench, I'm just having some trouble communicating with it. I know the MS itself is operating as the FP output goes true for about two seconds upon powerup and then goes off (priming pulse), I just can't get my laptop to talk to it. I'm not seeing any activity on the Three LEDs, but I'm guessing that's normal for a baseline-configured MS2.
Currently I'm using the new serial adapter that came with your package, I think tonight I'll try using it to talk to my MS, and/or use my RS-232 adapter to talk to yours.
Currently I'm using the new serial adapter that came with your package, I think tonight I'll try using it to talk to my MS, and/or use my RS-232 adapter to talk to yours.
Reply
0
0
07-15-2008, 04:18 PM
#12
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,020
Total Cats: 6,588
I used the tiny little driver CD that came in the package with the serial cable, and the adapter subsequently populated itself into my Device Manager tree. I changed it from COM8 to COM1 (which is unused) and configured the port for 115200, leaving all the other defaults such as 8N1, the buffers, etc.
I may simply test it with a null modem and a terminal program to one of my other known-good machines to validate the operation of the port. I expect that perhaps I'm missing something in the MegaTune config, which I've only just started tinkering with for the MS2.
BTW, Sam- can we sneak an addition into the car name somewhere? I'm thinking of The #51 SM2 SystemStrategies.com/DIYAutoTune.com Mazda Miata presented by UNC Law. I'll try to get you a hat.
I may simply test it with a null modem and a terminal program to one of my other known-good machines to validate the operation of the port. I expect that perhaps I'm missing something in the MegaTune config, which I've only just started tinkering with for the MS2.
BTW, Sam- can we sneak an addition into the car name somewhere? I'm thinking of The #51 SM2 SystemStrategies.com/DIYAutoTune.com Mazda Miata presented by UNC Law. I'll try to get you a hat.
Reply
0
0
07-15-2008, 05:36 PM
#14
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,020
Total Cats: 6,588
Uhm, yeah... Chris... You'd think I could remember your name, given your choice of username and whatnot... 
As to custom embroidered sombreros, here you are: http://www.asipinatas.com/Sombreros/index.htm
As to custom embroidered sombreros, here you are: http://www.asipinatas.com/Sombreros/index.htm
Reply
0
0
07-15-2008, 06:10 PM
#15
Junior Member
Thread Starter
iTrader: (1)
Join Date: Jul 2006
Location: Colorado
Posts: 402
Total Cats: 2
Uhm, yeah... Chris... You'd think I could remember your name, given your choice of username and whatnot...
As to custom embroidered sombreros, here you are: http://www.asipinatas.com/Sombreros/index.htm
As to custom embroidered sombreros, here you are: http://www.asipinatas.com/Sombreros/index.htm
Reply
0
0
07-15-2008, 07:45 PM
#16
I was looking into this some time back for the same reasons. Could be a fun project. The FlexFuel sensors were a little pricey but I got the impression that there were used ones to be had (though one model tended to fail?). My main snag was wrapping my head around moving from MS1 to MS2 at the time (getting all of the miata mods converted). I was busy so I gave up - would still love to do it. A lot of e85 to be had in Indiana.
Certainly watching this thread.
Certainly watching this thread.
Reply
0
0
07-15-2008, 11:39 PM
#17
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,020
Total Cats: 6,588
Success.
Started by validating the serial adapter itself. Used a null modem to connect directly to another PC and was able to have a terminal session between them at both 9600 and 112500.
Next, used the 'scope to verify that serial data was in fact getting all the way to pin 38 of the CPU (the actual 9S12C64) when I tried communicating, but was getting nothing back on pin 39. No activity in MT, wouldn't pass the "test" in the comm setup screen.
Yet all this time I know the CPU is alive, because I see activity on the FP line for ~2 seconds at startup...
Finally gave up and re-flashed the MS with the new MS2-Extra code, and now I can finally communicate with it. Man... Two days down and I haven't touched the hardware yet.
Anyway, Chris, I think we're finally in business. I'm going to try to get the cam input triggers done tomorrow. If I can get to the point where I see an RPM indication, I'll be happy. Gotta figure out how to configure an NA CAS in MS2. The wheel decoder in this software is way different from what I'm used to.
Started by validating the serial adapter itself. Used a null modem to connect directly to another PC and was able to have a terminal session between them at both 9600 and 112500.
Next, used the 'scope to verify that serial data was in fact getting all the way to pin 38 of the CPU (the actual 9S12C64) when I tried communicating, but was getting nothing back on pin 39. No activity in MT, wouldn't pass the "test" in the comm setup screen.
Yet all this time I know the CPU is alive, because I see activity on the FP line for ~2 seconds at startup...
Finally gave up and re-flashed the MS with the new MS2-Extra code, and now I can finally communicate with it. Man... Two days down and I haven't touched the hardware yet.
Anyway, Chris, I think we're finally in business. I'm going to try to get the cam input triggers done tomorrow. If I can get to the point where I see an RPM indication, I'll be happy. Gotta figure out how to configure an NA CAS in MS2. The wheel decoder in this software is way different from what I'm used to.
Reply
0
0
07-16-2008, 11:43 PM
#18
Boost Pope
iTrader: (8)
Join Date: Sep 2005
Location: Chicago. (The less-murder part.)
Posts: 33,020
Total Cats: 6,588
Good news, Chris- your MS2 is officially Squirting and Sparking.
I built the CAS input and ignitor output stages this evening and just got done testing them. The circuit is a bit of a hybrid- for the inputs I built the 4G63 circuits exactly as spec'd in the MS2Extra docs, including the second phototransistor circuit: http://www.msextra.com/ms2extra/MS2-...4g63.htm#2hall
For the spark outputs, I deviated from the MS2E docs and built them to MS1 spec, using Q6 and Q8 with 5v pullups through 100Ω on the collector side, as I'm more familiar with this circuit and I know it works on both the stock igniter and the COPs.
So I've got good activity on both spark outs, and both INJ outs (I haven't modified those, and don't plan to.)
Now it's decision time. I've got to find a place to mount the two big FETs for IAC and WI control. I've already removed and tossed Q16, the high-current ignition driver, as it's worthless in this application. So I need to make one more space on the heatsink. I'll give you the choice here- I can either remove R37 & R38 which will defeat the injector overcurrent protection circuit, or I can remove Q9 & Q12, which will defeat the ability to run Lo-Z injectors. I'm leaning towards pulling the resistors- their job is to prevent you from doing something stupid like putting four Lo-z injectors on one channel and blowing up the FET, removing them won't affect the functionality of the system.
I built the CAS input and ignitor output stages this evening and just got done testing them. The circuit is a bit of a hybrid- for the inputs I built the 4G63 circuits exactly as spec'd in the MS2Extra docs, including the second phototransistor circuit: http://www.msextra.com/ms2extra/MS2-...4g63.htm#2hall
For the spark outputs, I deviated from the MS2E docs and built them to MS1 spec, using Q6 and Q8 with 5v pullups through 100Ω on the collector side, as I'm more familiar with this circuit and I know it works on both the stock igniter and the COPs.
So I've got good activity on both spark outs, and both INJ outs (I haven't modified those, and don't plan to.)
Now it's decision time. I've got to find a place to mount the two big FETs for IAC and WI control. I've already removed and tossed Q16, the high-current ignition driver, as it's worthless in this application. So I need to make one more space on the heatsink. I'll give you the choice here- I can either remove R37 & R38 which will defeat the injector overcurrent protection circuit, or I can remove Q9 & Q12, which will defeat the ability to run Lo-Z injectors. I'm leaning towards pulling the resistors- their job is to prevent you from doing something stupid like putting four Lo-z injectors on one channel and blowing up the FET, removing them won't affect the functionality of the system.
Reply
0
0
07-17-2008, 09:15 AM
#19
Junior Member
Thread Starter
iTrader: (1)
Join Date: Jul 2006
Location: Colorado
Posts: 402
Total Cats: 2
Good news, Chris- your MS2 is officially Squirting and Sparking.
I built the CAS input and ignitor output stages this evening and just got done testing them. The circuit is a bit of a hybrid- for the inputs I built the 4G63 circuits exactly as spec'd in the MS2Extra docs, including the second phototransistor circuit: http://www.msextra.com/ms2extra/MS2-...4g63.htm#2hall
For the spark outputs, I deviated from the MS2E docs and built them to MS1 spec, using Q6 and Q8 with 5v pullups through 100Ω on the collector side, as I'm more familiar with this circuit and I know it works on both the stock igniter and the COPs.
So I've got good activity on both spark outs, and both INJ outs (I haven't modified those, and don't plan to.)
Now it's decision time. I've got to find a place to mount the two big FETs for IAC and WI control. I've already removed and tossed Q16, the high-current ignition driver, as it's worthless in this application. So I need to make one more space on the heatsink. I'll give you the choice here- I can either remove R37 & R38 which will defeat the injector overcurrent protection circuit, or I can remove Q9 & Q12, which will defeat the ability to run Lo-Z injectors. I'm leaning towards pulling the resistors- their job is to prevent you from doing something stupid like putting four Lo-z injectors on one channel and blowing up the FET, removing them won't affect the functionality of the system.
I built the CAS input and ignitor output stages this evening and just got done testing them. The circuit is a bit of a hybrid- for the inputs I built the 4G63 circuits exactly as spec'd in the MS2Extra docs, including the second phototransistor circuit: http://www.msextra.com/ms2extra/MS2-...4g63.htm#2hall
For the spark outputs, I deviated from the MS2E docs and built them to MS1 spec, using Q6 and Q8 with 5v pullups through 100Ω on the collector side, as I'm more familiar with this circuit and I know it works on both the stock igniter and the COPs.
So I've got good activity on both spark outs, and both INJ outs (I haven't modified those, and don't plan to.)
Now it's decision time. I've got to find a place to mount the two big FETs for IAC and WI control. I've already removed and tossed Q16, the high-current ignition driver, as it's worthless in this application. So I need to make one more space on the heatsink. I'll give you the choice here- I can either remove R37 & R38 which will defeat the injector overcurrent protection circuit, or I can remove Q9 & Q12, which will defeat the ability to run Lo-Z injectors. I'm leaning towards pulling the resistors- their job is to prevent you from doing something stupid like putting four Lo-z injectors on one channel and blowing up the FET, removing them won't affect the functionality of the system.
I think Q9 and Q12 can go.
Reply
0
0
