2 BAR Tuning Setup and RTT Questions

[1156248781]

Disclaimer: I legitimately tried to search for the answers to these questions before posting! If I missed something somewhere, please post a link! Thanks!

I have an '04 CTS-V with an Edelbrock E-Force unit installed and have converted over to the 2 BAR OS. I ditched the Bosch T-MAP in favor of the 2 BAR Cobalt sensor as it is a direct plug in and does not require scaling from what I have been able to find (it was also cheaper than the T-MAP connector harness from Ford).

Anyhow, I have everything converted over and have the correct fuel injector data and adjusted the TB scaler for the 90mm unit in place of the 78mm. It starts and runs at idle and I am about to begin tuning, however this is where I have a few questions:

1. The MAF fail must be set to "0 Hz" and DTC's P0102 and 103 must be set fail on first error with the "CEL" box unchecked. Is this still true if the MAF is no longer even in the system? Will the OS recognize there is no MAF input and simply run SD with the DTC's set to "No Error Reported"? This is half a tuning question and half an emissions testing question.

2. Is using the RTT as accurate as using a wideband? Is it recommended to use the RTT to get "close" and then switch to the wideband error PID to get things exact? I assume RTT maps the VE tables in much the same way as it finds the ST/LT correction factors...is this correct?

3. When using RTT, must you still complete all of the traditional tuning steps? Force open loop operation, disable PE, reset the O2 readiness monitors, etc? Or, is all of this compensated for through this process?

Appreciate any info that can be provided! Thanks in advance!

[Beatdown Z]

RTT just brings up tables and allow you to change them on-the-fly, seeing the results immediately. It's not a self-tuning feature or anything like that.

Set the MAF DTC's to fail on first error or no mil light. On my truck i have it set to no mil light...

Do NOT disable PE! Get your wideband installed if it's not already and log afr/lambda error. You can then tune the VE using RTT and copy and paste it to your tune when done.

[robbyredneck]

can you post your current converted tune?

[1156248781]

Here's the tune, I still have not begun to make any changes at this point. I took what I could from the available cells out of my old Maggie tune and interpolated the rest in order to have a baseline that was a little closer than what the carried over OE values were.

I thought the whole idea was to stop the PCM from making adjustments/changes to the maps while tuning in order to prevent trying to hit a moving target? Is this no longer the case?

[robbyredneck]

beatdown covered it. your maf fail is set up fine but you could set your airflow vs freq table to zero. also look at your pe/be tab. i am not too familiar with supers (mostly turbos)but you will have two tables to work with when it comes time to dialing in your enrichment under power then boost. your ve looks pretty robotic and much fatter at idle and off idle than moving so pay attention there. you just need to get your ve error table workin' and do not disable pe you can factor your error with be/pe built in. there is still no practical substitute for the wide band . rtt is just a time saving function so you don't have to flash scan flash scan etc.

[1156248781]

Many thanks for your review's! That was the tune that I am about to load in order to begin tuning...all I have right loaded now is just enough for it to start up and idle to check for leaks, ensure the T-stat is working, no fuel leaks, etc.

I installed a bastardized E-Force 2300 onto the LS6, so I had a bit of making things work as I went along. The car is extremely lean at the moment, even with very slow throttle transitions just off idle so I fudged the VE tables based off what was available from my Maggie tune (which was an OE 1 BAR/MAF tune).

I'll roughly set the PE/BE tables and let the fun begin! Just to be clear here...I am still supposed to setup everything else the same, am I correct? Force open loop, etc?

Thanks again, much appreciated!

[robbyredneck]

60 lb injectors with returnless? i would add 15-20 % on your ve from 1600 rpm and up. i will send you a ve AS AN EXAMPLE. DO NOT LOAD AND RUN

[1156248781]

Well, RTT does not work for me. Every time I try to make an adjustment it corrupts the scanner and shuts it down. Oh well...would have been nice if it worked for me although I guess I don't need to be spoiled, LOL.

[denmah]

did you enable RTT in the tune file before connecting?

[DrLoch]

Also you had better change your BE, it's currently set at 1.

[chevyalltheway]

I've read on here before. Turn car to on, do not start. Start the scanner and open RTT. After loading then start the car. I personally do not have that problem but someone else did and theirs started working.

Good luck,
-Kyle

[1156248781]

did you enable RTT in the tune file before connecting?

Yeah, I did. BTW - nice to see you over on these forums, I follow your stuff on Tech and am pretty impressed with what some "good ole' boy" engineering can produce.

I've read on here before. Turn car to on, do not start. Start the scanner and open RTT. After loading then start the car. I personally do not have that problem but someone else did and theirs started working.

Good luck,
-Kyle

Thanks! I will give this a go. Just my luck that I am one of the few to have issue's, LOL!

Most of the issue's that I had and could not resolve were ultimately resolved by completing a second complete "write entire" re-flash. So if anyone's having sketchy issue's with a tune that you had to complete a "write entire" to execute, try that first.

The car runs really well now but I need a new HEX pump, which will now be my third. Once I get this straightened out and my IAT's in line, I'm sure I'll be back asking for more advice.

[chevyalltheway]

Hex pump?

[1156248781]

Yeah, I have a liquid air-water intercooler built into the supercharger to lower the charge air temps. There is an electric pump that circulates the coolant through the intercoolers and the heat exchanger (HEX) out in front at the lower grill opening.

[chevyalltheway]

Sexy . Hope you the best of luck.