Speeduino is now on Github Sponsors (Rather than Patreon): https://github.com/sponsors/noisymime
Help with building your Speeduino, installing it, getting it to run etc.
User avatar
By PSIG
#37019
DaveyB wrote:
Fri Aug 09, 2019 12:36 pm
…can extra columns be added through manipulating the software? Just wondering as the idle is normally around 1200rpm for my engine on carbs and don't want to lose the flexibility around the 6000rpm mark when the power valves start to move and the pipe starts to work which change the engine characteristics.
As now stated, the values and increments of load and rpm may be configured to suit your application best, as briefly described in the Wiki: https://speeduino.com/wiki/index.php/Tu ... e_VE_Table

David
By TZ350
#37023
DaveyB wrote:
Fri Aug 09, 2019 12:36 pm
looking at the 16 column fuelling table it shows the fuelling starting at 3000rpm. This is probably a question for PSIG, but can extra columns be added through manipulating the software? Just wondering as the idle is normally around 1200rpm for my engine on carbs and don't want to lose the flexibility around the 6000rpm mark when the power valves start to move and the pipe starts to work which change the engine characteristics.
.
Hi Davey. You are stuck with 16 rpm columns but they don't have to be evenly spaced. The trick is to select rpm points that allow you to have evenly stepped changes in fuel load. You can bunch up rpm points where things are changing rapidly like when the motor is getting on the pipe and the torque curve is increasing steeply and space the rpm points out where the torque curve is flatter.
.
By TZ350
#37026
.
The steps between RPM and TPS points does not have to be even. The trick is to position them so that the fuel "Load" steps between cells is smooth as possible, no big jumps.

Typically the RPM steps follow the Torque curve and some of the RPM steps are bunched together in the rpm area where the torque curve is steepest as the motor is getting on the pipe. The idea is to keep the increasing fuel steps as even as possible as the RPM changes.

The graph is a typical carburetor flow curve. I tested my ball valve inlet and got the green line. 50% of air flow is typically at 25% throttle open. So at least half the fuel steps need to be below the 25% throttle line to get the increasing fuel demand steps due to the steadily increasing air flow as even as possible.

The point is RPM and TPS steps can be uneven, its the steps between Fuel load cells that need to be as even as possible.

I have got the dam picture upside down again ..... #$##**%^$%^ ........ :?
.
Attachments
25% Area (1).jpg
25% Area (1).jpg (796.67 KiB) Viewed 2013 times
User avatar
By DaveyB
#37054
Hi TZ and PSIG,

OK, so we're stuck with the 16 columns. I understand matching the spacing to the engine demand and at certain rpms the engine will be acting mostly linear. Therefore, the steps can be more non-linearly spaced.
A question for PSIG.
As Speedy is fixed, could it run two maps consecutively and have the ability to automatically jump between the two depending on certain engine conditions?
TZ, when looking at your VE table, it looks like you've only allocated 6 columns from 3000 to 7200 rpm for the crankcase pressure differential measurement, whilst giving 10 columns to Alpha N from 7800 to 13500 rpm? I thought that the area (in rpm) below where the pipe starts working would require finer control and thus more columns. I know on my carb'd race engine, I've set the idle to just over 3000rpm whilst the same road engine is at 1200 rpm.

On a separate note are you running the engine with premix or oil pump?
User avatar
By PSIG
#37058
DaveyB wrote:
Mon Aug 12, 2019 12:30 pm
As Speedy is fixed, could it run two maps consecutively and have the ability to automatically jump between the two depending on certain engine conditions?
Not currently. I would not judge the value by the number of cells, as unlike older systems that needed a zillion cells to choose-from; Speeduino does not "hop" from one cell to the next, but rather it smoothly interpolates from multiple surrounding cells at any given moment when determining fuel delivery (or ignition timing). That effect is multiplied by the ability to alter resolution in any area with uneven custom spacing. Bunch some extra rows and columns where your engine goes on-pipe for tight control at that point, and see how it does.

David
By TZ350
#37098
DaveyB wrote:
Mon Aug 12, 2019 12:30 pm
TZ, when looking at your VE table, it looks like you've only allocated 6 columns from 3000 to 7200 rpm for the crankcase pressure differential measurement, whilst giving 10 columns to Alpha N from 7800 to 13500 rpm? I thought that the area (in rpm) below where the pipe starts working would require finer control and thus more columns. On a separate note are you running the engine with premix or oil pump?
.
Premix. 20:1.

No, the area below (and above) the transition area where the pipe starts to work does not need as many columns as the transition area itself.

I have abandoned the VE map approach and for now are concentrating on Alpha-N multiplied by the MAP/Baro ratio.

Alpha-N is great for everywhere the airflow is consistent. So Alpha-N is good for everywhere that is not on the pipe and every where on the pipe and above 50% TP throttle position. There is only a smaller area where Alpha-N does not work well and that is in the area where you could be on the pipe and less than 50% TP. That is because air flow here is variable due to inconsistent pipe action.

Currently my crankcase PseudoMAP outputs a MAP value equal to the Baro value in the areas where airflow is going to be consistent. So the Alpha-N map here is multiplied by the ratio of 1:1 i.e., Alpha-N * 1.

And in the area where the engine should be on the pipe but the TPS is less than 50% the PseudoMAP outputs three times the Delta crankcase pressure. So in the variable air flow area the Alpha-N map is multiplied by ratio of PseudoMAP : Baro. i.e., Alpha-N * (PseudoMAP/Baro).

Anyway this is the current approach I am exploring, I will find out soon if the concept works. If Speedy gets a table that switches between AN and VE maps according to TPS vis RPM then I will try working with both maps again.
.
Attachments
Area where AN is multiplied by MAP Baro ratio.jpg
Area where AN is multiplied by MAP Baro ratio.jpg (1.66 MiB) Viewed 1913 times
By TZ350
#37409
PSIG wrote:
Sat Aug 03, 2019 2:51 am
Because rolling back has not fixed the issue, I would do an EEPROM wipe to clear any leftovers possibly there. Load one of the firmwares and try again. David
.
I did the eeprom wipe, completely new firmware (old but proven version) and new tune but I am still plagued by this thing randomly stopping. Its as if the power to the board quits. It seems to stop injecting and then stops firing through a lack of fuel (separate ignition system) then goes of line on the Tuning Studio screen. Starts right up again after Tuning Studio re connects.......... :!:

I will try the recovery routine again and work through it carefully. If that does not fix it, I guess I best start looking at the hardware. This has run reliably before but now there is a naughty gremlin in the system somewhere.... :|
.
By TZ350
#37624
.
Ok, wiped it all and re loaded everything, totally new project and it still has problems.
.
(52.02 KiB) Downloaded 53 times
.
1)Difficult to start, only starts with a dose of Start-You-Bastard, no pulse width or rpm displayed during cranking. Cranking speed should be high enough to register on the rpm gauge and certainly I would expect to see some pulse width.

2)Once running, it runs well for a short period 10-30 sec's then stops. The ignition is separate from the Speedy and it is obvious that injection has stopped because there is the tell tail pickup in rpm as the crankcase dries out. At which point TS goes off line. It re connects quite quickly and the engine can be re started.

Any suggestions of things to look for would be very welcome....... :P
.
User avatar
By PSIG
#37626
TZ350 wrote:
Thu Sep 05, 2019 7:46 am
1)Difficult to start, only starts with a dose of Start-You-Bastard, no pulse width or rpm displayed during cranking.
This is what throws a twist into the mix. :?
TZ350 wrote:
Thu Sep 05, 2019 7:46 am
2)Once running, it runs well for a short period 10-30 sec's then stops.
My approach on troubleshooting stuff like this is to check the silly simple stuff first. "Is is plugged-in?" kind-of stuff, but which can also give clues while testing if the issue is deeper.

For example, I would test for what location the failure begins (break in the chain). I would use a 'scope or even DMM to test the power stability going into Speedy. All good? Then move to the regulator and test again at cutout. Continue this series until it gets to the output of the processor for injectors and finally the MOSFET outputs. Somewhere in that test series, it must fail or falter. That allows deeper digging specifically at and immediately before that point if the problem is not yet obvious, and it could be hardware or software-based — but now I know where to focus in that chain.

For clarity; how many injector channels are you using? If multiple, do they all fail simultaneously? Does TS disconnect simultaneously? Any other common traits at failure?

David
  • 1
  • 36
  • 37
  • 38
  • 39
  • 40
  • 42
ATmega2561?

Here the PCB files of the last version. I think,[…]

gewitterbox

gewitterBOX (low-cost and mini-sized ECU for spe[…]

Honda B16A2 Trigger patterns

Make yourself a single tooth cam trigger and run a[…]

Toyota 3S-GE - what to buy?

As JHolland said, your ECU will take state values […]

Still can't find what you're looking for?