Need help with 6.0 L92/L76

[Josh_luther]

I just swapped out my 5.3 for a 6.0 with a 232/236 112+2 cam and L92 heads with l76 intake and 90 mm TB.

I'm having a hard time getting it to start and idle. It will only start if I give it some throttle and it only idles when it wants to. Sometimes it will idle for a minute and then stall and some times it won't idle at all. I can't put it in gear with out two footing it. Here is the current tune and a log file using Russ's Idle config. Any help would be appreciated TIA

[Russ K]

Try this tune. You need to do the idle scan from a cold start in park till operating temp. Then use my Maf tune config file and drive the truck around, then post these 2 scan logs.

Do you have a shift kit & Corvette servo in your trans? If not your trans won't live long as you disabled all the upshift torque reduction, and you have less than stock shift pressures in some torque cells. Also your TCC max & min tables should be 100 & 90 respectively.

Your main spark tables are too high, about 22* - 24* timing at wot would put you in the range.

Post the stock 6.0L tune, as I just compared your's to a 2004 Silverado SS. There may be some differences between your stock tune that you used and the one I downloaded from the tune repository.

Russ Kemp

[Josh_luther]

Russ it's much better. Thank you. It did how ever stall a few times once at 120* and then when it got to 192* it wouldn't stay running.

I can do the MAF scan but my LC-1 doesn't read to accurate with the Hptuners as I have it wired to the rear O2. With the 1 volt signal I'm having a hard time dialing it in. I am going to switch it to the egr wire at the pcm.

I will re-adjust the timing tables a little lower on the high side.

My tranny is a fully built 4l60e but I still don't think it's gonna last long behind this motor. My old H/C N2O 5.3 put down 440rwtq but I think this motor will do that NA.I was considering putting some Tq management back in.

I used a 04 6.0 tune out of the repository but the Lq9 tune you used is probably a better start. The compression of this motor is slightly higher 2cc smaller chambers and .040" head gaskets.

Thanks Again Josh

[Russ K]

Try this tune, I raised the idle speed 50 rpm & added 1 gram of running airflow. I also added 4* base idle timing. Do a scan with the Maf config file first after flashing this tune. Then do a cold start idle scan the next day. The fuel trims will help tell how the tune is.

Russ Kemp

[Josh_luther]

Russ the idle is again much better. Here is an idle log from cold start and a log using your MAF config. I couldn't go for a ride because it is really icy out.