The MegaSquirt Project has experienced explosive growth other the years, with hundreds of new MS installations occurring every week - a phenomenal success! MegaSquirt has been successfully used in all aspects of Internal Combustion engine applications including R&D, Industry, Race, and Research. The MS project has transformed itself from a simple R&D project into a full-featured mature engine control system. To reflect this the support structure has also changed to meet the needs of MegaSquirt Users.
Moving forward, the R&D forums for MegaSquirt project are in a read-only mode - no new forum posts are accepted.
However the forums will remain available for view, they still contain a wealth of information on how MegaSquirt works, how it is installed and used. Feel free to search the forums for information, facts, and overview.While the R&D forum traffic has slowed in recent years, this is not at all a reflection of Megasquirt users, which continue to grow year after year. What has changed is that the method of MegaSquirt support today has rapidly moved to Facebook, this is where the vast majority of interaction is happening now. For those not on Facebook the msextra forums is another place for product support. Finally, for product selection assistance, all of the MegaSquirt vendors are there to help you select a system, along with all of the required pieces to make it complete.
A forum for discussing applications and implementations of the MegaShift transmission controller code for the GPIO from B&G. This can control up to 8-speeds and 6 shift solenoids (plus a 16x9 table for controlling a PWM line pressure valve). It has manual and fully automatic modes (16x9 load x speed table), with under and over rev-limit protection, and full data logging of all inputs and outputs (among many other abilities). A TransStim to test your completed board is also available.
So here are the instructions from Jake's Performance on my 4L80E trans brake:
Wiring the transbrake consists of tying into the B wire, typically yellow wire, that controls the B (2-3) shift solenoid on the control harness going to the transmission.
Go through a momentary switch to a good ground.
Activating the switch in the manual low position will engage the transbrake.
PCM tuning required. You must program the controller to not allow a 1-2 shift while the transmission is in manual low.
The transbrake will engage if the PCM commands an upshift causing parts damage or injury.
We also do not recommend downshifting into manual low while moving.
Our transbrake design allows for very fast transbrake setup and release times as well as minimizes circuit volume in several circuits in the transmission. This makes it very quick acting and capable of holding more HP on the transbrake and clutches. As a byproduct of the design, it applies the low gear band quicker than the intermediate (2nd) gear clutches can release, creating a slight bind on a 2-1 downshift. We can alter this for those that need the ability to do 2-1 downshifts.
Any suggestions on how to set this up properly so Megashift doesn't cause the trans to kill itself
It sounds like you want to prevent the 1-2 shift using the gear lever. Is "manual low" normally 1st gear or second gear (1.e. first and second gears)?
If manual low is normally first gear, the controller will not shift to second (unless you have rev limit checking on and you exceed the limit, but you can turn the limiting off or set the limit to an out-of-range value).
If manual low is second gear normally (and possibly allows shifts to 1st), you could tell MShift that the gear lever input pattern for manual low is the pattern for first gear (even though it might normally be 1st and 2nd in the OEM scheme). Then the trans won't shift to second (with the same caveat about rev limiting, which you can turn off if you like). This would mean you wouldn't have a lever position that selected only 1st and 2nd, but that's what you want if I understand correctly.
The other thing you can do is shift manually using the shift buttons.
BTW, I am thinking of implementing a third shift m,ode (besides auto and manual) that would be a lever follow mode (except possibly in the highest gear lever position). That seems to be what a number of people are looking for (instead of using the shift buttons). This will be released in the code update thread when it is ready for prime time.
Lance.
"Never wrestle with pigs. You both get dirty and the pig likes it." - George Bernard Shaw
I noticed something odd about manual low....when I moved the wratchet shifter all the way down to what should be 1st, the gear indicator still showed 0. It definitely was in first as I was able to drive the car and it didn't shift out of first, but then when I wratched up to 2nd, the car didn't shift as Megashift now was commanding first gear?
Attached is the MSQ. I was driving the car for the first time last night and noticed something weird.
If I used the wratchet shifter to go down into 1st gear and then wratcheted up back into drive, it would not shift gears. It was not until I came to a complete stop and then put it in Drive (4) that it would shift normal again. I don't have any datalogs YET but I will hopefully by tonight.
I noticed something odd about manual low....when I moved the wratchet shifter all the way down to what should be 1st, the gear indicator still showed 0. It definitely was in first as I was able to drive the car and it didn't shift out of first, but then when I wratched up to 2nd, the car didn't shift as Megashift now was commanding first gear?
Found the problem.....I was checking to see if I installed the 330ohm pullup (I did) and noticed that on the build instructions the diode goes the other way for the circuit on input 1. Swapped it and it now recognizes all 4 gears
