Typical VE numbers
08-15-23, 02:11 AM
#26
Rotary Enthusiast
turn off the flow % table you dont need it.
i only ever use that when mapping things like old nascar motors that have 16 injectors (8 at the port and 8 above the trumpets) and we want to blend them in and out threw the rev range or you want to idle on the secondarys and then turn them off etc
set the staging duty cycles to say 30% what that will do is run the primary injectors to 30% duty then it will bring the secondary's in to 30% then both stages will increase together at the same duty cycle
if you put 30% in the primary and then 80% in the secondary it will hold the primarys at 30% until the secondarys reach 80% then will bring the primarys up to 80% and both will go up together from there
but the simplest way is to put them both at a number and go from there, when you have the dead times correct you cannot even tell when they come on, i have done a 2 rotor with 4 stages and bringing the last stage on at 35psi boost you couldnt even see the AFR change
i would raise the whole dead time table together. you will know when you have gone too far as you will loose control of the injector at idle and moving the ve numbers by 15 wont do anything but you will be more than double your current numbers before you even get close to that happening
i only ever use that when mapping things like old nascar motors that have 16 injectors (8 at the port and 8 above the trumpets) and we want to blend them in and out threw the rev range or you want to idle on the secondarys and then turn them off etc
set the staging duty cycles to say 30% what that will do is run the primary injectors to 30% duty then it will bring the secondary's in to 30% then both stages will increase together at the same duty cycle
if you put 30% in the primary and then 80% in the secondary it will hold the primarys at 30% until the secondarys reach 80% then will bring the primarys up to 80% and both will go up together from there
but the simplest way is to put them both at a number and go from there, when you have the dead times correct you cannot even tell when they come on, i have done a 2 rotor with 4 stages and bringing the last stage on at 35psi boost you couldnt even see the AFR change
i would raise the whole dead time table together. you will know when you have gone too far as you will loose control of the injector at idle and moving the ve numbers by 15 wont do anything but you will be more than double your current numbers before you even get close to that happening
08-15-23, 08:52 AM
#27
So I played with the dead times last night. Turned off any corrections and set ~9 cells around idle with 40% values. It actually needed ~0.3 added to the primary dead times to get here (nice call). I found it much harder to dial things in at this point, though. The AFR would fluctuate much more than before and neighboring cells did not seem linear, but this is with the car in the garage just using some throttle and driveline resistance to get the crosshair centered on the cell.
I dialed it back to ~0.2 added and everything seemed to sharpen up. Reacts more like it did with my original settings. Its much more linear and from what I can see, the map is flattening out significantly. I imagine it would look more like one of the screenshots above when complete.
Seems like slightly more fluctuation on a single cell but hard to say, I shouldn't have a problem to get it dialed in. I'm in the 50% region at idle here, but it seemed to have a significant improvement higher up. I was reducing the high rpm values quite a bit (looks like under 100 up top) so I think I might stick with this for now.
One thing I did notice is that this setup favors a pretty rich mixture. I gave it a little blip with 0.3 added before leaning it out and it sounded MEAN. I saw a 9 on the wideband, but damn, I think I will richen up my target table a bit..
I guess I failed to mention earlier that my primary injectors are in the LIM. Didn't think it would effect the VE #s, but I'm also not an expert. That change anything?
Now before I go and retune the car, what is the consensus on Alpha-N? Have heard some good things, so if I am starting fresh is it worth consideration?
Thanks again!!!
I dialed it back to ~0.2 added and everything seemed to sharpen up. Reacts more like it did with my original settings. Its much more linear and from what I can see, the map is flattening out significantly. I imagine it would look more like one of the screenshots above when complete.
Seems like slightly more fluctuation on a single cell but hard to say, I shouldn't have a problem to get it dialed in. I'm in the 50% region at idle here, but it seemed to have a significant improvement higher up. I was reducing the high rpm values quite a bit (looks like under 100 up top) so I think I might stick with this for now.
One thing I did notice is that this setup favors a pretty rich mixture. I gave it a little blip with 0.3 added before leaning it out and it sounded MEAN. I saw a 9 on the wideband, but damn, I think I will richen up my target table a bit..
I guess I failed to mention earlier that my primary injectors are in the LIM. Didn't think it would effect the VE #s, but I'm also not an expert. That change anything?
Now before I go and retune the car, what is the consensus on Alpha-N? Have heard some good things, so if I am starting fresh is it worth consideration?
Thanks again!!!
08-15-23, 03:47 PM
#28
So I played with the dead times last night. Turned off any corrections and set ~9 cells around idle with 40% values. It actually needed ~0.3 added to the primary dead times to get here (nice call). I found it much harder to dial things in at this point, though. The AFR would fluctuate much more than before and neighboring cells did not seem linear, but this is with the car in the garage just using some throttle and driveline resistance to get the crosshair centered on the cell.
I dialed it back to ~0.2 added and everything seemed to sharpen up. Reacts more like it did with my original settings. Its much more linear and from what I can see, the map is flattening out significantly. I imagine it would look more like one of the screenshots above when complete.
Seems like slightly more fluctuation on a single cell but hard to say, I shouldn't have a problem to get it dialed in. I'm in the 50% region at idle here, but it seemed to have a significant improvement higher up. I was reducing the high rpm values quite a bit (looks like under 100 up top) so I think I might stick with this for now.
One thing I did notice is that this setup favors a pretty rich mixture. I gave it a little blip with 0.3 added before leaning it out and it sounded MEAN. I saw a 9 on the wideband, but damn, I think I will richen up my target table a bit..
I guess I failed to mention earlier that my primary injectors are in the LIM. Didn't think it would effect the VE #s, but I'm also not an expert. That change anything?
Now before I go and retune the car, what is the consensus on Alpha-N? Have heard some good things, so if I am starting fresh is it worth consideration?
Thanks again!!!
I dialed it back to ~0.2 added and everything seemed to sharpen up. Reacts more like it did with my original settings. Its much more linear and from what I can see, the map is flattening out significantly. I imagine it would look more like one of the screenshots above when complete.
Seems like slightly more fluctuation on a single cell but hard to say, I shouldn't have a problem to get it dialed in. I'm in the 50% region at idle here, but it seemed to have a significant improvement higher up. I was reducing the high rpm values quite a bit (looks like under 100 up top) so I think I might stick with this for now.
One thing I did notice is that this setup favors a pretty rich mixture. I gave it a little blip with 0.3 added before leaning it out and it sounded MEAN. I saw a 9 on the wideband, but damn, I think I will richen up my target table a bit..
I guess I failed to mention earlier that my primary injectors are in the LIM. Didn't think it would effect the VE #s, but I'm also not an expert. That change anything?
Now before I go and retune the car, what is the consensus on Alpha-N? Have heard some good things, so if I am starting fresh is it worth consideration?
Thanks again!!!
Why not in the block?
08-15-23, 04:31 PM
#29
Rotary Enthusiast
yep your primary injectors in the LIM is going to suck... put them into the centre plate.. it 100% effects the way your throttle transitions work and as you saw when it was richer it was better that is because it got the right amount of fuel into the motor but so much fuel is getting stuck to the walls of the runners and flowing through after you release the throttle..
do not change your target afr to get it to transition nice.
you are trying to tune idle with all the fuel getting stuck to the walls of the runners thats why when you leaned it out it sucked.. fix the injector placement and watch how much more you will need to add to the dead time to get it right
do not change your target afr to get it to transition nice.
you are trying to tune idle with all the fuel getting stuck to the walls of the runners thats why when you leaned it out it sucked.. fix the injector placement and watch how much more you will need to add to the dead time to get it right
08-15-23, 04:33 PM
#30
Long story short, there's a clearance issue with my Xcessive LIM. I had interference between the primary and secondary rail, with no quick or easy solution that sits well with me. I ran it as is / jammed up with 6 injectors for 10 years but it always bothered me..
It was my intention to make the current setup as simple as absolutely possible, and one fuel rail helped in that department. I know its not ideal, but coming from carbs and wraparound manifolds; figured I could make it work.
It was my intention to make the current setup as simple as absolutely possible, and one fuel rail helped in that department. I know its not ideal, but coming from carbs and wraparound manifolds; figured I could make it work.
08-17-23, 10:52 AM
#33
Specific mechanical issues of OP's vehicle aside, there is a sort of philosophical discussion going on here. Basically, what do you change when the theoretical values don't get the final result? Where does the fudge factor come in? Is it changing injector related settings, changing target AFR, changing VE table? For what it's worth, I've seen and done multiple approaches here, and everybody on the internet likes to argue.
What it comes down to, is that there are theoretical or averaged values, such as the deadtimes or injector flow characteristics (flow at given deadtime and fuel rail pressure). Those deadtimes typically come from some averaged population of injectors and there will be production tolerances. The volumetric efficiency can actually be measured if you can accurately calculate the airflow into the engine (needs a mass airflow sensor, or precise fuel flow meter + air/fuel ratio measurement). There is also closed loop compensation. There's also target air fuel ratio tables.
There is always some kind of fudging built into a tune to account for individual engine differences and real world vs theoretical/nominal specification. You can bake that into the deadtime calculation, the VE table, the target AFR, the feed forward compensations (skewing the air temperature, water temperature, wall wetting compensation), and to some extent the closed loop fuel control. Even in stock ECUs with very sophisticated mapping based on physics there is still fudging going on. In a Nissan GT-R or other Nissan stock ECU for example, they adjust AFR's by having a look up table to compensate the mass airflow sensor reading based on rpm and throttle position.
You can swear by adjusting the deadtime or some other method, but each has its trade offs. Any change to the base injector settings (size, deadtime, etc) can throw off the entire tune. You have to finalize this value at some point and leave it alone. Otherwise you will be chasing your tail. The experienced tuners here understand this, and nobody is advocating endless iterations of injector trial-and-error. A novice is going to go around in circles if they do things in the wrong order and they may not realize it.
What's my preferred method? It depends on the situation of course, but in general I've got no problem with keeping manufacturer recommended injector settings. Then I'll skew target AFR tables. I can also tolerate some closed loop variation. You don't want to go too far out of range for any of these things, but it's total optimization problem. There's always side effects and risks to be managed in any tuning decision.
What it comes down to, is that there are theoretical or averaged values, such as the deadtimes or injector flow characteristics (flow at given deadtime and fuel rail pressure). Those deadtimes typically come from some averaged population of injectors and there will be production tolerances. The volumetric efficiency can actually be measured if you can accurately calculate the airflow into the engine (needs a mass airflow sensor, or precise fuel flow meter + air/fuel ratio measurement). There is also closed loop compensation. There's also target air fuel ratio tables.
There is always some kind of fudging built into a tune to account for individual engine differences and real world vs theoretical/nominal specification. You can bake that into the deadtime calculation, the VE table, the target AFR, the feed forward compensations (skewing the air temperature, water temperature, wall wetting compensation), and to some extent the closed loop fuel control. Even in stock ECUs with very sophisticated mapping based on physics there is still fudging going on. In a Nissan GT-R or other Nissan stock ECU for example, they adjust AFR's by having a look up table to compensate the mass airflow sensor reading based on rpm and throttle position.
You can swear by adjusting the deadtime or some other method, but each has its trade offs. Any change to the base injector settings (size, deadtime, etc) can throw off the entire tune. You have to finalize this value at some point and leave it alone. Otherwise you will be chasing your tail. The experienced tuners here understand this, and nobody is advocating endless iterations of injector trial-and-error. A novice is going to go around in circles if they do things in the wrong order and they may not realize it.
What's my preferred method? It depends on the situation of course, but in general I've got no problem with keeping manufacturer recommended injector settings. Then I'll skew target AFR tables. I can also tolerate some closed loop variation. You don't want to go too far out of range for any of these things, but it's total optimization problem. There's always side effects and risks to be managed in any tuning decision.
Last edited by arghx; 08-17-23 at 12:31 PM.
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1badFB (08-17-23)
08-17-23, 12:07 PM
#34
This one has been a brain twister for me, as there is obviously more going on in the background with a VE calculation involved. My biggest concern is that I don't have enough experience to determine what these calculations affect, and figuring it out through trial and error sounds like a painful process.
I had a totally drivable base tune with the high VE #s, no noticeable issues in tuning progression but the numbers just didn't sit well.
https://support.haltech.com/portal/e...ctor-dead-time
This article supports the dead time argument based on VE #s alone, but interesting to note is the overall shape of the map when the dead times are adjusted. My original table had a shape that looked correct, but was high across the board. I thought for sure this would have been a fuel pressure or sensor issue, but those check out so injector characterization is next up.
While I suspect I could have carried on with the original configuration and been mostly fine, I like the dead time adjustment as that should be baked in to any possible hidden calculations where some other adjustments might not. Obviously there are extremes (as shown in the Haltech article), but dead times look like the only adjustment to smooth out the "normal" linear nature of the VE map. Once I have the injector placement sorted out, I'm going to play a bit more and see what settings make it look the most linear. I believe the additional pulse width through dead time will have the greatest effect down low, and if the VE ramps back up again it could be improper flow #s.
I was really hoping to avoid putting the injectors back in the block, but it should be easier to rule out other issues once I've done that. Hopefully I can get it back together before the season is over, cant wait to post some successful results.
Cheers
I had a totally drivable base tune with the high VE #s, no noticeable issues in tuning progression but the numbers just didn't sit well.
https://support.haltech.com/portal/e...ctor-dead-time
This article supports the dead time argument based on VE #s alone, but interesting to note is the overall shape of the map when the dead times are adjusted. My original table had a shape that looked correct, but was high across the board. I thought for sure this would have been a fuel pressure or sensor issue, but those check out so injector characterization is next up.
While I suspect I could have carried on with the original configuration and been mostly fine, I like the dead time adjustment as that should be baked in to any possible hidden calculations where some other adjustments might not. Obviously there are extremes (as shown in the Haltech article), but dead times look like the only adjustment to smooth out the "normal" linear nature of the VE map. Once I have the injector placement sorted out, I'm going to play a bit more and see what settings make it look the most linear. I believe the additional pulse width through dead time will have the greatest effect down low, and if the VE ramps back up again it could be improper flow #s.
I was really hoping to avoid putting the injectors back in the block, but it should be easier to rule out other issues once I've done that. Hopefully I can get it back together before the season is over, cant wait to post some successful results.
Cheers
08-17-23, 01:21 PM
#35
Now, fuel pressure wise - your fuel pressure regulator is able to bypass enough fuel right? is your base pressure holding consistently? What is the base pressure set to? 43.5 psi with regulator disconnected, or something else? How did you set the pressure?
That being said If everything is too high, or you want to shift it lower, than that could easily just mean adjusting your air temperature compensation. Or even changing the injector size, if your flow rate is lower than nominal value. Everything will have a side effect though. I'm not saying there is any exact one way to do it, or that changing the deadtime is "wrong"... just that injector setting changes throws everything off. It's a big impact. You can throw your whole fuel tune out the window when you change anything injector or fuel pressure related. By that I don't mean literally that the entire tune always needs to be redone when you change any injector setting at all. It means you now have to verify everything is ok again, or simply assume everything is ok and hope nothing pops up later (idle, tip in response, hot starts, AFR's as weather changes, etc). That's why at some point you have to freeze the setting. You have to say "I'm done, I'm committed, and from here on out, I am not changing fundamental characteristics of the tune without starting over from scratch"
Bandaids and fudge factors aren't a "good" thing. But if you don't draw a line in the sand and lock down certain parameters, you'll never get anywhere. That necessitates workaround later (skewing tables like target AFR, VE, etc), or making a difficult decision to scrap and start over. Every time you change injector settings you are basically gutting your house back to the frame or foundation, whatever metaphor you like.
That being said If everything is too high, or you want to shift it lower, than that could easily just mean adjusting your air temperature compensation. Or even changing the injector size, if your flow rate is lower than nominal value. Everything will have a side effect though. I'm not saying there is any exact one way to do it, or that changing the deadtime is "wrong"... just that injector setting changes throws everything off. It's a big impact. You can throw your whole fuel tune out the window when you change anything injector or fuel pressure related. By that I don't mean literally that the entire tune always needs to be redone when you change any injector setting at all. It means you now have to verify everything is ok again, or simply assume everything is ok and hope nothing pops up later (idle, tip in response, hot starts, AFR's as weather changes, etc). That's why at some point you have to freeze the setting. You have to say "I'm done, I'm committed, and from here on out, I am not changing fundamental characteristics of the tune without starting over from scratch"
Bandaids and fudge factors aren't a "good" thing. But if you don't draw a line in the sand and lock down certain parameters, you'll never get anywhere. That necessitates workaround later (skewing tables like target AFR, VE, etc), or making a difficult decision to scrap and start over. Every time you change injector settings you are basically gutting your house back to the frame or foundation, whatever metaphor you like.
Last edited by arghx; 08-17-23 at 01:25 PM.
08-17-23, 01:55 PM
#36
Set to 43.5psi with fuel pump running and engine off.
Fuel pressure input is set to MAP Reference (and I have a fuel pressure sensor connected), so FP is referenced and differential pressure is steady so no concerns there.
Currently using "auto VE air temp correction" so I haven't played with corrections. Is this a bad idea? IAT reads ambient temperature with engine cold and calibration looks fine from what I can tell.
I'm just doing my best to process and make sense of what the more experienced members are telling me. I could lower the VE #s many ways (as you elude to) but I have no basis for that when everything appears correct so I'm leaning on y'all.
I think I have enough sense to grasp most of the concepts, just short on the practical application. Adding a bit of fuel to what is essentially the minimum injector pulse width seemed like a good start.
As much as I hate issues, these are the best kind as they bring up a lot of possibilities and make you look at the whole picture. While I would be further ahead if my VE table looked good in the beginning, I would have forged ahead on my own without any deeper thought. This has been a valuable discussion / though process for me. Not outta the woods yet, though!
Fuel pressure input is set to MAP Reference (and I have a fuel pressure sensor connected), so FP is referenced and differential pressure is steady so no concerns there.
Currently using "auto VE air temp correction" so I haven't played with corrections. Is this a bad idea? IAT reads ambient temperature with engine cold and calibration looks fine from what I can tell.
I'm just doing my best to process and make sense of what the more experienced members are telling me. I could lower the VE #s many ways (as you elude to) but I have no basis for that when everything appears correct so I'm leaning on y'all.
I think I have enough sense to grasp most of the concepts, just short on the practical application. Adding a bit of fuel to what is essentially the minimum injector pulse width seemed like a good start.
As much as I hate issues, these are the best kind as they bring up a lot of possibilities and make you look at the whole picture. While I would be further ahead if my VE table looked good in the beginning, I would have forged ahead on my own without any deeper thought. This has been a valuable discussion / though process for me. Not outta the woods yet, though!
08-17-23, 02:12 PM
#37
Air Temp Correction (haltech.com)
you can apply the auto compensation and then use this air temp correction table as a fudge factor for correction.
you can apply the auto compensation and then use this air temp correction table as a fudge factor for correction.
08-17-23, 04:26 PM
#38
Full Member
Set to 43.5psi with fuel pump running and engine off.
Fuel pressure input is set to MAP Reference (and I have a fuel pressure sensor connected), so FP is referenced and differential pressure is steady so no concerns there.
Currently using "auto VE air temp correction" so I haven't played with corrections. Is this a bad idea? IAT reads ambient temperature with engine cold and calibration looks fine from what I can tell.
I'm just doing my best to process and make sense of what the more experienced members are telling me. I could lower the VE #s many ways (as you elude to) but I have no basis for that when everything appears correct so I'm leaning on y'all.
I think I have enough sense to grasp most of the concepts, just short on the practical application. Adding a bit of fuel to what is essentially the minimum injector pulse width seemed like a good start.
As much as I hate issues, these are the best kind as they bring up a lot of possibilities and make you look at the whole picture. While I would be further ahead if my VE table looked good in the beginning, I would have forged ahead on my own without any deeper thought. This has been a valuable discussion / though process for me. Not outta the woods yet, though!
Fuel pressure input is set to MAP Reference (and I have a fuel pressure sensor connected), so FP is referenced and differential pressure is steady so no concerns there.
Currently using "auto VE air temp correction" so I haven't played with corrections. Is this a bad idea? IAT reads ambient temperature with engine cold and calibration looks fine from what I can tell.
I'm just doing my best to process and make sense of what the more experienced members are telling me. I could lower the VE #s many ways (as you elude to) but I have no basis for that when everything appears correct so I'm leaning on y'all.
I think I have enough sense to grasp most of the concepts, just short on the practical application. Adding a bit of fuel to what is essentially the minimum injector pulse width seemed like a good start.
As much as I hate issues, these are the best kind as they bring up a lot of possibilities and make you look at the whole picture. While I would be further ahead if my VE table looked good in the beginning, I would have forged ahead on my own without any deeper thought. This has been a valuable discussion / though process for me. Not outta the woods yet, though!
Air Temp Correction (haltech.com)
you can apply the auto compensation and then use this air temp correction table as a fudge factor for correction.
you can apply the auto compensation and then use this air temp correction table as a fudge factor for correction.
ARGHX, that was a perfect explanation of fudge factor for tuning. We try to keep this at a minimum, but there are certain things that call for it with particular setups. The number one cause of MORE of this (fudge factor) is fuel flow balance to the injectors, followed by regulation issues, and then pulsation damping issues (large spikes in differential pressure).
08-17-23, 04:45 PM
#39
Rotary Enthusiast
fixing the dead times is not fudging the tune..
the dead times supplied by injector resllers are incorrect for 99% of the applications.,
you can call it fudging all you like but its not,
the dead times supplied by injector resllers are incorrect for 99% of the applications.,
you can call it fudging all you like but its not,
08-17-23, 06:07 PM
#42
It's best to disable the Auto Air Temp Compensation and to actually build the Air Temp Correction Table, which a Haltech Basemap is close enough for most cars. Having this on AND not zeroing that table make for a funky correction and extra fudge packing...
ARGHX, that was a perfect explanation of fudge factor for tuning. We try to keep this at a minimum, but there are certain things that call for it with particular setups. The number one cause of MORE of this (fudge factor) is fuel flow balance to the injectors, followed by regulation issues, and then pulsation damping issues (large spikes in differential pressure).
ARGHX, that was a perfect explanation of fudge factor for tuning. We try to keep this at a minimum, but there are certain things that call for it with particular setups. The number one cause of MORE of this (fudge factor) is fuel flow balance to the injectors, followed by regulation issues, and then pulsation damping issues (large spikes in differential pressure).
Air Temp Correction table is zeroed out, and I made sure I don't have anything else stacked up.
I grew up with a powerFC so I know a thing or two about fudging.. why I want this setup nice and polished, haha
EGTs are dead nuts between rotors, i was a little surprised at that actually. 2c apart at idle with no cylinder correction.
I’ve got a radium FPD just ahead of CJ fuel rails, remote pressure sender piped direct to middle of the rail.
Really tried to put together something decent
08-17-23, 06:59 PM
#43
Rotary Enthusiast
08-18-23, 12:41 PM
#44
Again this is all a matter of your personal approach or philosophy. On domestic platforms for example you might keep a stock airbox and filter, stock MAF scaling settings, and swap the injectors. Then adjust the fuel slopes (sort of like deadtime tables) from some default values to bring your fuel trims in line. That doesn't represent the actual physical characteristics of the injectors though, although it could be very close. There are a lot of extra factors like changes in spray pattern, whatever. I call it fudging, which sounds like I'm knocking it, but you could just call it fuel tuning. Just understand that there are physical constants and there is the software equivalent of turning screws on a carb. Sometimes those two functions overlap, but they don't always have to, as long as you consider side effects. By no means am I saying anyone here is wrong. I'm just sharing my thoughts for the less experienced who want context.
In mass production stock tunes, these kinds of injector characterization numbers (flow, deadtime, whatever) generally represent an average of the sample of the parts. So when you tune a stock calibration (back when I was tuning for OEMs, now new engine designs are mostly bye bye), you get an engine and sensors, injectors, etc that are built to very precise tolerances that represent some kind of average of the expected production run. Then it's up to closed loop control (fuel trims, knock learning) to take care of the slack, assuming feed forward compensation (air and water temp tables, after start, etc etc) is good enough.
Last edited by arghx; 08-18-23 at 12:49 PM.
08-19-23, 12:41 AM
#45
Rotary Enthusiast
having access to a machine that measures dead times is still useless unless you are using your ecu, wiring harness, power supplies etc that you are using in the car..
this is where everyone goes wrong thinking that supplied data is correct, it is never correct for your application..
something as simple as the injector supply to the ecu not having the same power supply (ie the wire that supplies the injectors power supplies the ecu power to pin 26) as the injectors which is very very common will totally mess up the dead times,
i cannot even remember the last time i actually looked at supplied dead times when tuning an aftermarket ecu because every time i did put them in they were always way out and had to be changed anyway..
there is a lot of injector supply places that have made a lot of money of putting a stamp on an injector and spitting out some numbers that are useless..
this is where everyone goes wrong thinking that supplied data is correct, it is never correct for your application..
something as simple as the injector supply to the ecu not having the same power supply (ie the wire that supplies the injectors power supplies the ecu power to pin 26) as the injectors which is very very common will totally mess up the dead times,
i cannot even remember the last time i actually looked at supplied dead times when tuning an aftermarket ecu because every time i did put them in they were always way out and had to be changed anyway..
there is a lot of injector supply places that have made a lot of money of putting a stamp on an injector and spitting out some numbers that are useless..
08-19-23, 07:35 AM
#46
having access to a machine that measures dead times is still useless unless you are using your ecu, wiring harness, power supplies etc that you are using in the car..
this is where everyone goes wrong thinking that supplied data is correct, it is never correct for your application..
something as simple as the injector supply to the ecu not having the same power supply (ie the wire that supplies the injectors power supplies the ecu power to pin 26) as the injectors which is very very common will totally mess up the dead times,
i cannot even remember the last time i actually looked at supplied dead times when tuning an aftermarket ecu because every time i did put them in they were always way out and had to be changed anyway..
there is a lot of injector supply places that have made a lot of money of putting a stamp on an injector and spitting out some numbers that are useless..
this is where everyone goes wrong thinking that supplied data is correct, it is never correct for your application..
something as simple as the injector supply to the ecu not having the same power supply (ie the wire that supplies the injectors power supplies the ecu power to pin 26) as the injectors which is very very common will totally mess up the dead times,
i cannot even remember the last time i actually looked at supplied dead times when tuning an aftermarket ecu because every time i did put them in they were always way out and had to be changed anyway..
there is a lot of injector supply places that have made a lot of money of putting a stamp on an injector and spitting out some numbers that are useless..
according to haltech manual to power up the CAN wideband u tap into a power wire on ecu that I think powers the Injectors as well
08-19-23, 01:36 PM
#47
Spent some time yesterday and got the primary injectors back in. Set it up as 3 stages 1000\1000\2600, with the staging @ 30%, then had a good look over everything. I have the Haltech fuse box style harness and injectors are powered from that in case anyone is wondering. I'm fairly picky about wiring.
I had messed around with the old map a lot through this process so I grafted in some base map VE #s and increased the dead times until it ran ok. Did not take much to put me in the 50s at idle.
With the injectors in the manifold only, it favored some aggressive timing at idle. I was able to knock that back a bunch and noticed a ton of VE change with that bit too. I actually had to dial back the dead times it was so drastic.
Haven't driven it yet just yet but its lookin good (or at least better). Thanks guys!
*Also you also weren't kidding about the transients. I had to reel those waay back. I had it working okay with some healthy async and decay, doesn't feel much different but the software sure seems easier to manage.
I had messed around with the old map a lot through this process so I grafted in some base map VE #s and increased the dead times until it ran ok. Did not take much to put me in the 50s at idle.
With the injectors in the manifold only, it favored some aggressive timing at idle. I was able to knock that back a bunch and noticed a ton of VE change with that bit too. I actually had to dial back the dead times it was so drastic.
Haven't driven it yet just yet but its lookin good (or at least better). Thanks guys!
*Also you also weren't kidding about the transients. I had to reel those waay back. I had it working okay with some healthy async and decay, doesn't feel much different but the software sure seems easier to manage.
08-19-23, 05:23 PM
#48
Rotary Enthusiast
a lot of people forget to wire it up..it also powers the DBW and stepper circuits from memory
08-21-23, 12:19 PM
#49
So as a bit of a follow up, lots of unmucking happened once the car hit the road.
Ended up with .6ms added to the first two stages. I haven't worried about the deep areas too much yet but put .4ms on the third stage for good measure.
High 40% VE numbers at idle, and nothing too excessive on the top end yet.
Still just playing around but I've got some good protections in place and less afraid to move forward. So far so good, thanks all!
Ended up with .6ms added to the first two stages. I haven't worried about the deep areas too much yet but put .4ms on the third stage for good measure.
High 40% VE numbers at idle, and nothing too excessive on the top end yet.
Still just playing around but I've got some good protections in place and less afraid to move forward. So far so good, thanks all!