V1 Mikes Extended, Full Frame Goblin - 2009 Cobalt LS with 135k donor

[mike_sno]

Got my 3in pipe kit. Mufflers are still on the way. Need some routing ideas.

 

[mike_sno]

If I delete the Catalytic converter, what am I doing with the O2 sensor behind the catalytic converter?

Just put some resistors in the plug and keep the input at 1V?

 

[Gtstorey]

Omit it and turn off the related DTC's with HPT. Or just ignore the light. Should work on these although there are a few GM vehicles that doesn't work on. A resistor wouldn't trick it enough to do anything.

 

[Rauq]

If you want to pull the wires for the B1S2 HO2S out of the harness, you can.

I believe I've concluded that LSJ's do some very slightly weird things without the rear O2 that are, in the end, inconsequential, but can be confusing if you don't know what's going on. When idling, the computer will occasionally command a dip and then rise in Commanded AFR (like 30s at 12:1 and then 30s at 17:1) that I'm pretty sure is some B1S2 calibration or check routine that HP Tuners doesn't have access to turn off. I use it as an opportunity to get comparative wideband data at idle as I'm logging fuel trims during CL operations and this routine will kick over to OL. Not a big deal, just weird and confusing if it comes as a surprise.

 

[mike_sno]

Awesome, thanks. I believe I saw a few settings in HPT Tuners, will look at those and deactivate them as well.

 

[mike_sno]

If you want to pull the wires for the B1S2 HO2S out of the harness, you can.

I believe I've concluded that LSJ's do some very slightly weird things without the rear O2 that are, in the end, inconsequential, but can be confusing if you don't know what's going on. When idling, the computer will occasionally command a dip and then rise in Commanded AFR (like 30s at 12:1 and then 30s at 17:1) that I'm pretty sure is some B1S2 calibration or check routine that HP Tuners doesn't have access to turn off. I use it as an opportunity to get comparative wideband data at idle as I'm logging fuel trims during CL operations and this routine will kick over to OL. Not a big deal, just weird and confusing if it comes as a surprise.

Ahh, can't wait on more thing screwing around with Idle

 

[Gtstorey]

On some of these, it is better to leave the o2 plugged in and turn off the DTC's. It's not unusual that you see some test trying to run and some of these are based upon it seeing the o2, not whether the o2 is actually seeing good data.

 

[mike_sno]

Ok, I can also just put a 2nd bung in the exhaust and have it stick in the exhaust.

 

[Gtstorey]

Ok, I can also just put a 2nd bung in the exhaust and have it stick in the exhaust.

You can always use it to swap in a Wideband.

 

[mike_sno]

Continuing to tune my idle. I think my VE table is off in the idle fields. Anyone having a log file where the engine is idels good and has VE and dynamic airflow logged?

 

[Chris_WNC]

Back to the downstream O2 sensor…I’m finishing up my remote tune with ZZP and early on they asked me if I could plug mine back in. The computer was having issues with some self tests, as mentioned above, and it was messing with data. I welded in a third bung and installed it using one of those cheater spacers.

 

[mike_sno]

I have all o2 sensors installed. Both narrow bands and the wb.

 

[mike_sno]

Installed the new exhaust and made another test, all knock is gone! This is stock stage 1 timing. All knock filtering is stock. Now lets see how much I can push it.

 

[Rauq]

If you want to do spark tuning, you'll need to create a Math parameter for cylinder airmass based off of dynamic airflow. Unfortunately the P12 doesn't have a PID build in for the vertical axis of the spark table. Keep in mind though on an FI engine you'll probably reach peak torque before you start knocking, whereas on an NA motor typically they will start knocking before peak torque is reached.

 

[Gtstorey]

In other words, don't keep bumping it up until you see knock and then turn it back just a little. You won't gain anything.

 

[mike_sno]

Ok, thanks for letting me know, adding more timing until I see knock was my original strategy. I won't be able to tell a difference on street tuning anyway. I was scheduled for a dyno session a few weeks back, but the guy canceled. Thank god, otherwise I would have tuned it with the old exhaust. (Wasn't planning on building a new one, but oh well, plans change)

I will get on schedule with another dyno guy out of town soon. That will hopefully also eliminate my annoying idle issue which it seems to be impossible for me to get under control.

On another note: I should not see sunlight in the transmission mount, or? I noticed that when I changed the angle of the gopro while recording the new bracket.

 

[Desert Sasqwatch]

That's bad. New mounts are needed - recommend getting the solid motor mounts from DF since you are making more HP.

 

[Rttoys]

I would do solid mounts. No real need for the engine/trans to move at all.

 

[mike_sno]

Well, lucky me. I had some parts left over. One was the desired mount http://dfkitcar.com/forum/index.php?threads/left-over-parts-from-engine-swap.4857/post-98342.

However, when I took the old mount apart, it was only secured with one screw and this screw was not even tight. If you look in the video around second 18 you can see the complete mount tilting down. Oh well, not the first time that I discovered that. http://dfkitcar.com/forum/index.php...009-cobalt-ls-with-135k-donor.4634/post-97182

I wonder if the screws dropped out over time. Could not have been recently, since I have some aluminum sheet blow the subframe.

I will drive the goblin tomorrow morning if its not raining. Want to weld a support bracket for the upper exhaust.

 

[mike_sno]

Just looking at the motor mounts again. Not knowing how it is in a Cobalt. But in the Goblin the engine is directly screwed to the frame on the upper side mounts. The Subframe is connected with the rubber mounts. Since I see the engine moving in my video, wouldn't that mean the the frame is flexing? I think it scetch up some solid mounts for the back and mill me some solid aluminum mounts. Another project....