Fuel Injector Chat and Discussion

[soxfan143]

Originally Posted by Str8JDM

anybody have a DIY or write up on crushing the stock regulator?

You need the FPR crush jig that comes with the Comptech SC. Because you are only supposed to crush it very little. It probably could be done without it but it would be really tough.

[Str8JDM]

Originally Posted by soxfan143

You need the FPR crush jig that comes with the Comptech SC. Because you are only supposed to crush it very little. It probably could be done without it but it would be really tough.

damn, i guess i need to try to find one

[EvansTuningDotCom]

Originally Posted by mucter

Yeah, once I get my AEM WBO2 installed, I'll definitely be tuning my car in straight open loop. It's by far the quickest/easiest way to do it. It'd be nice if Hondata would give us the ability to disable closed loop without losing the readings from the sensor.

You already can, just think outside of the box with the software.

[mucter]

Originally Posted by EvansTuningDotCom

You already can, just think outside of the box with the software.

2 things I can think of here....

Set the short trim min and max to 0.

and/or

Disable my primary, install the WBO2 in it's place and tune off the datalogs from that.

[Supa Ninja]

Alright, I'm going to ping this off you'alls heads. I couldn't get my greddy based map to startup. I put the 1000cc map in(I got my FP from Evans Tuning). It fired right up. Well I went back through it and put the dead times that came with my injectors for the base pressure I'm running. It doesn't start when it's below 50, I'm lean as **** up top, and my duty cycle is high as hell.

Basically my car likes the latency times that are on the base map. I don't know why but that's what's working. Needless to say it fired right up this morning with the base map latencies and it's in the 30's.

[EvansTuningDotCom]

Originally Posted by mucter

2 things I can think of here....

Set the short trim min and max to 0.

We have a winner!

[EvansTuningDotCom]

Originally Posted by Supa Ninja

Alright, I'm going to ping this off you'alls heads. I couldn't get my greddy based map to startup. I put the 1000cc map in(I got my FP from Evans Tuning). It fired right up. Well I went back through it and put the dead times that came with my injectors for the base pressure I'm running. It doesn't start when it's below 50, I'm lean as **** up top, and my duty cycle is high as hell.

Basically my car likes the latency times that are on the base map. I don't know why but that's what's working. Needless to say it fired right up this morning with the base map latencies and it's in the 30's.

What are your IDC with the basemap default dead times and without? The dead times will significantly effect cold start and idle.

[Tony1]

This happens often. Changing dead times has a significant affect on fuel flow at low pulsewidths.

DO NOT CHANGE THE DEAD TIMES TO CORRECT A TUNE!!!!

Set the dead times to the correct value and then adjust the fuel tables to achieve your desired a/f ratio.

If your car ran better with the dead times wrong then the fuel map is wrong.

[mucter]

I was going to say this... the 1000cc basemap in FPM is based on the stock latency. It's not using ID's latency values. It would be good for there to be a new one made based on the correct latency values.

I'm planning to build my calibration off the correct values, but it'll be so tuned for my car that I don't think it'll be helpful to anyone else.

[Tony1]

Originally Posted by Hondata
All RC injectors are tested at 43.5 psi. In our injector calibrations the we needed to remove 15% fuel from the 750cc calibration to run the ID 1000cc injectors at the same air fuel ratio. That would place the ID1000 injectors at approximately 860cc as compared to the RC 750s. (we did not flow test these injectors)


This is another common misconception.

Here's the deal and WHY correct injector dead times are important.

Nobody tunes with the correct dead times unless they're using ID injectors because nobody else provides them.

If you have a 1000cc injector with a .5ms dead time and an injector pulsewidth of 1.5ms.

You swap that injector for a different 1000cc injector that has a 1ms dead time and you don't correct for it then you still have a 1.5ms pulsewidth. EXCEPT, you are using another .5ms with this injector with no fuel flow because the dead time is double. So the effective pulsewidth of the old setup was 1.0ms and the effective pulsewidth of the new setup is .5ms. Both are 1000cc injectors but the new injector is 50% leaner at idle. Make sense?

1.5ms open time - .5ms dead time = 1ms effective
1.5ms open time - 1ms dead time = .5ms effective

THIS is why you could go from a small injector to a big injector and actually have to add fuel at low pulsewidths, because the dead time makes up such a big percentage of total fuel flow at low pulsewidths. If everyone used correct dead times, you'd never see situations like that, but the reality is that's not what goes on in the world. Eventually everyone will understand the importance and pay attention to having correct injector data.

You should never use the required percentage change to calculate the fuel flow of an injector, especially if the correct dead times are not used. The other variable there is how the reflash stuff calculates the percentage change. I don't know the details on it, but there have been many times where i've asked for a 10% change in overall fuel trim with Hondata and not received a 10% change in a/f ratio like i should.

[mucter]

Originally Posted by Tony1

THIS is why you could go from a small injector to a big injector and actually have to add fuel at low pulsewidths, because the dead time makes up such a big percentage of total fuel flow at low pulsewidths. If everyone used correct dead times, you'd never see situations like that, but the reality is that's not what goes on in the world. Eventually everyone will understand the importance and pay attention to having correct injector data.

I've been preaching this for quite some time. Unfortunately, like you said, the data for the proper dead times at the proper fuel pressure just doesn't exist for most injectors... so tuners have gotten used to either fixing the latency themselves based on the way the car -feels- or just ignoring it and using the VE tables to compensate.

It sucks. I'm looking forward to installing my ID injectors this weekend and tuning my fuel PROPERLY.

[soxfan143]

Originally Posted by Tony1

Originally Posted by Hondata
All RC injectors are tested at 43.5 psi. In our injector calibrations the we needed to remove 15% fuel from the 750cc calibration to run the ID 1000cc injectors at the same air fuel ratio. That would place the ID1000 injectors at approximately 860cc as compared to the RC 750s. (we did not flow test these injectors)


This is another common misconception.

Here's the deal and WHY correct injector dead times are important.

Nobody tunes with the correct dead times unless they're using ID injectors because nobody else provides them.

If you have a 1000cc injector with a .5ms dead time and an injector pulsewidth of 1.5ms.

You swap that injector for a different 1000cc injector that has a 1ms dead time and you don't correct for it then you still have a 1.5ms pulsewidth. EXCEPT, you are using another .5ms with this injector with no fuel flow because the dead time is double. So the effective pulsewidth of the old setup was 1.0ms and the effective pulsewidth of the new setup is .5ms. Both are 1000cc injectors but the new injector is 50% leaner at idle. Make sense?

1.5ms open time - .5ms dead time = 1ms effective
1.5ms open time - 1ms dead time = .5ms effective

THIS is why you could go from a small injector to a big injector and actually have to add fuel at low pulsewidths, because the dead time makes up such a big percentage of total fuel flow at low pulsewidths. If everyone used correct dead times, you'd never see situations like that, but the reality is that's not what goes on in the world. Eventually everyone will understand the importance and pay attention to having correct injector data.

You should never use the required percentage change to calculate the fuel flow of an injector, especially if the correct dead times are not used. The other variable there is how the reflash stuff calculates the percentage change. I don't know the details on it, but there have been many times where i've asked for a 10% change in overall fuel trim with Hondata and not received a 10% change in a/f ratio like i should.

for Tony! Good to see you on here man. Great info right there.

[BlueSi4]

So, all the information that Tony provided, how does that affect someone that's running ID1000cc injectors and is getting tuned? Is there a difference as far as what the tunner can do with those injectors compared to another set of injectors? I'm a little lost with it

[mucter]

ID supplies the correct dead times (opening times or latency as it's also called) for a large range of voltages and fuel pressures. None of the other injector manufacturers do this.

This allows your tuner to tune your fuel properly... instead of just compensating for the wrong dead times through tuning the fuel tables. It'll give you better closed loop operation. (better idle, less erratic fuel trims, better fuel economy)

[BlueSi4]

Originally Posted by mucter

ID supplies the correct dead times (opening times or latency as it's also called) for a large range of voltages and fuel pressures. None of the other injector manufacturers do this.

This allows your tuner to tune your fuel properly... instead of just compensating for the wrong dead times through tuning the fuel tables. It'll give you better closed loop operation. (better idle, less erratic fuel trims, better fuel economy)

Thank you for that, you put it simple enough for me to understand

[Supa Ninja]

Originally Posted by EvansTuningDotCom

What are your IDC with the basemap default dead times and without? The dead times will significantly effect cold start and idle.

The base map already had the 1000cc inj selected and 6v/3162 8v/2116 10v/1450 12v/1092 16v/684

I'm running base fuel pressure of 60psi so I used that map
8v/3195 10v/1880 12v/1440 14v/1080 16v/845

I've tried it with the inj cc set to 1000 and 1180 as per my specs.

It starts up just fine, Im holding boost. I haven't had a chance to do a 3rd gear pull, but with the dead times that caused the cold start problems I wasn't keeping boost and I was having high IDCs plus I was running really lean.

I'm not trying to reinvent the wheel, I just want to know what I'm doing wrong.

Btw I'm running 3mm HG and a fuel return.

[Supa Ninja]

Here is my latest and greatest datalog....I already addressed the rich mid-range and richened the top just a smidge.



Up top i was just 66% at 14psi. Damn i'm still loosing boost.

[maiku]

Would this help me with my cold start issues? It takes over 7 seconds to start no matter what I've tried.
GReddy kit with 650cc RC's and walbro FP.
FPR is NOT crushed. Would that help?

[BlueSi4]

Mine is fine even when the temperatures have been around 20 degrees....

[Supa Ninja]

well i just uploaded the greddy base map that i got 293/266 edyno with 1000cc selected and the default latencies. Fired up no problem, I'm totally baffled. My precision inj worked just fine with the latency time that precision gave me.

Don't be messing with your latency times just yet guys. this isn't the right way to fix anything but in my case its the only solution i have been able to find.