V1 More Questions about Fuel Injectors

[ctuinstra]

I have the Siemens DEKA 60lbs injectors. They are rated for 60lbs/hr @ 43.5 PSI (645cc/min @ 3 BAR). But our car has a a 4 BAR fuel regulator from what I have always seen on the fuel pressure gauge. The ECM was tuned for the 60lbs but if it's running 58psi on the fuel rail, it has to be tuned wrong from ZZP. I assume this might be the reason for the running rich issue and poor idle. But surely I must be wrong, I cannot be the only one that has run into this. Am I missing something here.

I'm going with the boost referenced fuel pressure set up just so it's easier to tune and I'm going to turn the pressure down from 4 BAR (58psi) to 3 BAR (43.5psi) so the larger injectors work better at idle.

I just feel like I'm missing something.

 

[Ross]

What is the problem Chad? Have you installed a wideband O2 sensor, and gathered some log files while it is driving?
60lbs/hr injectors can be run at various fuel pressures, and run various BAR fuel regulators, long as the ECM tuning is done correctly.
The two items don't have to match. Your 60lb injectors will be more like 70lb injectors at the higher fuel pressures.
The idle issue is a known problem with running the Siemens DEKA 60lbs injectors, and your boost reference fuel pressure will help clean that issue up, maybe even eliminate it.

 

[ctuinstra]

Well the "tune" from ZZP is for 60lbs when they actually flow higher at the higher fuel pressure. The ECM is limited to the same 60lbs flow rate.

For instance, of the manifold vacuum is at 80kPa, the chart below assumes a flow rate of 61.2lbs (this flow is based upon 3 BAR) but this car actually has a fuel pressure of 4 BAR so the actual flow is much higher.

So to enter correct information, one would have to know the actual flow rate given the fuel pressure for the manifold vacuum.

 

[ctuinstra]

Oh, and yes, I have a wideband and the HP Tuners Scanner is showing the car running pig rich much of the time and the LTFT max out at some points. I also have a occasional backfire (not just pop) just after lifting.

 

[Ross]

Lets re-tune your engine (ZZP didn't lock your ECM did they? If yes, buy another ECU, or get ZZP to unlock & remove their tune.)
I'm not sure if HP Tuners can change the manifold vacuum table to a 4 bar.
If we can, great. If we can't, we can still let the ECM think it has a 3 bar, and tune MAF table anyhow.
After MAF tuning, we can do VE tuning, then spark.
That is as far as I have gotten, but my car was running great after this.

 

[Karter2026]

Well this does not sound promising for me and my supercharger add on. I ordered the 60lb injectors on black Friday.

 

[ctuinstra]

Well this does not sound promising for me and my supercharger add on. I ordered the 60lb injectors on black Friday.

They can work. Many have them and say they work well. But the need to be tuned properly and I have many questions about how ZZP tuned them..

 

[Karter2026]

They can work. Many have them and say they work well. But the need to be tuned properly and I have many questions about how ZZP tuned them..

I have a tune file for a 09 2.2LAP with a SC add on. It had 60lb and was running a bigger (3.4") pulley I am looking at running a 3.0 I also have a 2.8 pulley.

 

[Ross]

Chad,
For your new boost reference fuel regulator, you could bench test the injectors at various manifold air vacuum/pressures, and measure the fuel injector flow rates (pain in the butt to set up/or costly to get some else to do)
OR
You could use your wideband O2 sensor to tune the injector flow rates in the manifold vacuum kPa table. (Easy)

When you tune the engine, you start by putting the PCM in open loop, and gathering the error rate between the PCM's requested air/fuel ratio, and the wideband's observed air/fuel ratio. You gather these errors based on the table you plan to adjust. For your new boost reference fuel pressure regulator, you could just gather the errors (by manifold vacuum kPa) and adjust the injector flow rate in the manifold vacuum kPa table (by % error observed).

 

[Richyrich91]

I have a tune file for a 09 2.2LAP with a SC add on. It had 60lb and was running a bigger (3.4") pulley I am looking at running a 3.0 I also have a 2.8 pulley.

Can you help me with a tune file? I just bought HPTuners and I have an 2010 2.2 LAP and I just put on the LSJ s/c, 2.8” intense pulley, and 60lb injectors. But I can’t seem to find a base tune or any tune with those mods. Can you possibly send me your tune?