Twin Turbo CTS-V help

I need some help from some of the experts on here. In 2008 I put twins on my 2005 V (LS6 with 317 heads) and the stock short block didn't last very long. I just finished putting together a forged 383, PRC stage 2.5 LS6 heads and a Comp Cam (228 I, 232 E duration .588 I .595 E lift, 114 LSA), 80 lb Siemens injectors, stock LS6 intake and ported stock throttle body. I added a 2 BAR MAP and threw together a base tune to get it started. It ran decent but was pig rich and had a slight stumble on throttle tip in. I went with a COS and that is when my troubles started. It will try to start but won't ever kick off and run. I flashed the initial start tune in again and it fired off and ran.

Please someone who is more of an expert than myself HELP!!!


Attached is my initial start tune and the COS tune.

Attachment 11478Attachment 11479

Hi gotabav,

In the COS file fix these out-of-range tables: A0001, A0002, A0012, A0013.

Then here is the problem why it does not run:
B3647 and B3649 are very incorrect... you have set them to AFR values but with EQR units (see pic, observe units in upper right of 3D table display, observe the cell values... 14.81 EQR is supper-hyper-beyond-wet rich :) );

Do this: Edit->Properties->Commanded Fuel Values and set it to EQR and restart the tunetool... from now on work only in EQR, avoid AFR (make yourself a cheatsheet)... and you now have to rework B3647 and B3649.

Attachment 11481

Do you really need almost max pressure at low torque for each shift...? :)

B3601 is wrong.

Set B3618 to suitably rich values, your have CL/trimming enabled... when you're in CL and PE triggers, B3618 commands fueling, not B3647.

When you're in OL and PE triggers, the richer of B3647/B3649 or B3618 commands fueling, in which case it is ok to set PE to stoich and command suitably rich in the last few columns of B3647/B3649... but it is simpler to just set B3618 suitably rich (i.e. same value as the last two columns of B3647).

Remember: do this all in EQR units.

Joe, you are the man! I will try this stuff out later today. I've tuned quite a few cars, but this is the first one using a COS, so this is uncharted territory for me. Thanks again!

Quote:

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Originally Posted by joecar

Do you really need almost max pressure at low torque for each shift...? :)

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It's a manual trans, I didn't touch the trans tables. No need to, correct?

Oh it's manual trans, then ignore the trans tables.