2nd Gear Start option?

[mill3833]

Does MSShift have the capability to do 2nd Gear Start like some OEM systems do? What this does is command 2nd gear if the shifter is in M2, regardless of VSS.

I know it could be done with the 2nd shift table, but I already have plans for that (Race vs Street trims). During a burnout in the water box, it would be handy to have the trans start in 2nd. It just avoids an unnecessary 1-2 shift in the water box.

I was thinking a check box could be added in each shift table window like this:

[Bernard Fife]

mill3833,

The code can be shifted manually into 2nd gear and it should stay there. You would then have to switch to auto mode if you wanted to use the tables for shifting.

However, there is no separate second gear start function apart from the tables or shifting manually. It could be added easily enough, though, and I will look at this for future code once the current tissues are worked out. The best plan is probably to use an input that signals that the next start should be in second gear (or perhaps a user-specified gear if the gear lever is in a specified position and the speed is zero).

Lance.

[mill3833]

Lance,

I understand things are pretty busy right now. I just wanted to put this there as a future enhancement. I didn't wire-up the manual shift buttons, but I see how that would work. My 94 Camaro didn't have the 2nd gear start feature, but 2001 Silverados do. Am suspecting it is something useful if driving on ice or snow, where you want to do a soft start on a slippery slope.

Dave

[Bernard Fife]

Dave,

Yeah, I can see how this could be quite useful. Perhaps a user option like:

Lever in 2nd Start: 'Use 1st and 2nd' -OR- 'Use 2nd Only' ?

Lance.

[mill3833]

That would be great.

[Bernard Fife]

Dave,

Attached is 4.144 code that has a first cut at the burn-out mode. The is a user setting under 'General Settings -> Shift Factors -> Burnout Mode (D2) Usage' with the options to "Use 1st and 2nd" (default), or "Use 2nd Only (burnout mode)". The option only applies when in auto mode. If "Use 2nd Only (burnout mode)" is selected, then whenever the lever is in 2nd (aka. D2) the trans will stay in 2nd and not shift to 1st at all.

Enabling burn-out mode effectively makes the trans manually shifted with the lever in the 1st (since the highest gear will be 1st) and 2nd positions (burn-out mode), and then the trans will be automatically shifted according to the shift table if the lever is in 3rd or 4th (or higher if your trans has more gears).

I have not tested this function, and it likely needs more work, but I waned to get this out there to see if it is what you want.

Monitor_4144.abs.s19

(73.01 KiB) Downloaded 473 times

GPIO_MShift_4144.ini

(220.09 KiB) Downloaded 499 times

Lance.

[mill3833]

Lance,

Great! I'll give it a try tomorrow.

Is a new ini needed?

Just to clarify, with this new feature on, and Lever in D2, then mGear = tGear =cGear =2, right? And it won't upshift to 3rd gear, regardless of engine rpm, right? This is what I'd expect. ie, If I get distracted in the water box by a short skirt, and briefly lose track of the tach, bouncing into the MS3Pro rev limiter, well so be it. I don't want it upshifting to 3rd gear. That's what 3-stage Rev limit is for.

Thanks,
Dave

[Bernard Fife]

Dave,

Yes you need the new INI (otherwise the option won't appear in the menus).

this new feature on, and Lever in D2, then mGear = tGear =cGear =2, right?

Yes. Regardless of vehicle speed.

regardless of engine rpm, right?

It depends on whether you have the 'rpm checking' on, if your MShift rpm settings are higher or lower than your rev-limiter settings, and then even if the rpm checking is on and the rpm limit it is exceeded I am not 100% sure if it will shift to 3rd (in general the code is designed to shift in this case because the rev limit is designed to be the absolute maximum engine rpm allowed. However I need to try this on the bench to see how it behaves - the code might try to shift to 3rd but then immediately shift back to 2nd - if it does that I can certainly fix it in the code). But if you set the upper rpm limit higher than you will ever want to see in the burn-out box (or any other time), or disable rpm checking, it won't (or shouldn't) shift at all in burn-out mode.

Lance.

[mill3833]

Hi Lance,

Here's the 4144 "Burnout Mode" garage test, report #1.

Its raining here (May in Indy...) so I have the car on jack stands in the garage. First off, integration between MSShift and TS is pretty neat. I'm impressed you can make this type of functionality update to the system with just an ini file. Neat stuff.

So I tried the default setting first. The 4L60E shifted and reacted as expected with lever movement, as before. This is, of course, with Lever Error Reporting off.

Then I tried selecting the burn-out mode. With foot on the brake, as I slowly moved the lever from D4 to D3 to D2, when I got to D2, TS lost comms with MSShift. An error window came up that said, "TS has lost comms to MSShift. Comms to MSShift is disabled", or something to that effect. I pulled the MSShift fuse to reset it, and restarted TS. All was back to normal. I repeated the test, with the same results. I then reset things, and this time, from D4, briskly moved the lever into D1. No faults, TS stayed connected. Then I moved it up into D2. TS lost comms with MSShift.

For what its worth, my MSShift is talking to MS3Pro via CAN, then MS2Pro to laptop via bluetooth.

I was not recording log data at the time, as this was just the dry-run.

Regards,
Dave

[mill3833]

Report #2.

After fixing my comms issues and enjoying my new found flexibility of using USB cable, I data logged with attempting the burnout mode feature. I had TS directly connected to MSShift RS232, and as it did yesterday, as soon as I moved the lever to 2nd it lost comms to TS. Log file attached.

BTW, the USB cable is very stable, after doing the "Reload Recent Project" trick. As a robustness test, engine off, TS connected to MSPro and MSShift via CAN, I slowly moving TPS around as a heartbeat indication on TS and momentarily turned off igition (1 sec off) and back on, and TS immediately come back on-line. Much quicker than BT adapter. I tried this many times, and if you wait too long, TS screen goes gray, but even so, it comes back pretty quick. During all this time, no comms issues. So as good as it is to implement CRC checksum someday on CAN coms, I thought I'd mention this to you. It appears to be pretty robust.

Dave