Cobra LS6 Swap Tuning, WOT dropping out
Friend of mine put a crate ls6 motor in a shelby cobra replica with a 4l65E tranny. We are trying to get it tuned. Chevy dealer put a 2004 automatic base tune in the ecu and then I copied over the stock 2004 z06 timing and VE maps since it is an ls6. Car drives great, idles good, shifts good. The problem we are seeing is at WOT the car downshifts goes like hell to ~5500rpm then feels like he let off the gas, coast for about 1/2-3/4 second then pulls up to 5500 again, and repeats that. TPS signal is at 100% the whole time but it feels like he is pedaling it on and off. Looking at the logs I took I don't see anything out of the ordinary. No KR, maf signal looks good, etc. Any ideas what this could be? Torque management? Some wierd automatic thing? I've never messed with automatics. We did calibrate the VSS so the speed is correct. What should I log to start narrowing it down?
I'll post the tune file and logs tonight once I keep to my laptop. I'm at work. I would love to have someone look at them and see if there are other things to adjust with this swap. Since the ls6/4l65e were never together I had to piece together 2 maps so I might have missed something.
