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Hi Andre/fellow tuners,
I am currently in the process of setting up a haltech elite on to a vehicle but I have no clue where to get proper injector dead time/latency values as well as flow rate in order to properly set up the VE model in the elite. The injectors are the stock injectors fitted on the engine from the manufacturer. I have attached two photos of the injector with a couple numbers on them....did some basic Google searching with the numbers but came up empty handed. If anyone can help or point me in a direction to go it'd be appreciated.
Vehicle is a 2013 Suzuki Swift Sport chassis code ZC32S
I'm sorry to say that you're really going to struggle to get this sort of data for your injectors. There's nobody I'm aware of right now who is offering injector characterisation services to the public. A few ECU manufacturers such as MoTeC and Adaptronic are doing this so they can supply data for their ECUs but they aren't going to be interested in doing it for somebody else's ECU. It might be worth emailing Haltech and see if they have any data for these injectors though.
With the Haltech's fuel model being somewhat basic compared to some ECUs the requirements are also a little simpler. You will need to know the injector flow at a specific fuel pressure (generally 3 bar or 43.5 psi). This is pretty critical to the numbers that go into the VE table. Ideally we would like accurate dead time data too but without this I would suggest you use the default dead time table and use that. It won't be right and will have an affect on the tune accuracy but with no data you have few options. It's important to mention that dead time has a much greater affect at idle and small pulse widths and progressively less as the pulse width increases.
If you want to go further than this you can also tune the idle to a specific AFR and then disable the alternator to reduce the battery voltage. Once you've done this you can tweak the cells in the dead time table to get your AFR back on track. This still WONT give you an accurate dead time table but it's about the best you can expect without data.
Andre thanks a lot for the reply. Understood on all that you said. Some more questions though.
I have access to a professional grade injector flow test tool that can "flow" the injectors at a set pressure. I noticed you mentioned 43.5psi but this car has a returnless fuel system so should be operating at around 58psi correct? Should I flow them at 43.5 or 58? I have no idea what the stock fuel pressure is...I'm just going off your figures from what you said is the general rule of thumb for map referenced/returnless systems.
Secondly, I observed on the haltech elite webinar when you went over VE model, you set the dead time tables and fuel flow tables as 3D tables....would this be necessary or can we use simple 2D tables?
Unfortunately more than the injector plays a role in deadtime. There is zero set correct number on this. You have the two major variables which are fuel pressure and injector driver of the hardware itself. Then the strategy used by the ecu.
Run dead time numbers at whatever fuel pressure is available to you. You will not need to alter fuel pressure until you approach max dc. When you do raise the boost the difference will be obvious and although its not scientific I would first try a blanket percentage adjustment based on what you see in trims after raising it. Then verify as much as you can.