LQ4 swap peaking at 5300 rpms on dyno and should peak around 6000 rpms based on cam

[brharris27317]

I have been fighting with this LQ4 setup for a while now off and on and I cant figure out what i am doing wrong with the programming. The LQ4 has GMPP CNC ported LS3 heads part number 88958758 using a stock LS3 intake, fuel rails and injectors with a 92mm cable operated throttle body which does open 100% by gas pedal and a howards 190295-12 camshaft which is 218/224 duration @ .050 with .604/.604 lift and 112 LSA. Long tube headers and dual 3.0" exhaust to dynomax ultra X muffler. engine runs and drives great and has about 25k miles on it now. but I just know it has more in it. I have video of the dyno pull and dyno graphs on I have done other builds and typically this type configuration will pull 10-15% more hp than torque but since that power is flat lining at 5300 rpms the hp and torque are nearly identical. since the compression ratio is still low being a LQ4 with those heads, I dont expect it to pull as much power as a true LS3 with that camshaft but it should still make at least 10% higher horsepower numbers and peak at 6000 rpms. I just dont know if there is some torque management or abuse mode setting that I have overlooked in the programming or something. Any help would be appreciated.

[Fast4.7]

What are you running for valve springs? The last engine I had fall off hundreds of RPMs before it should have, had weak springs. Also check you WOT manifold pressure vs barometric pressure. If you have a substantial high rpm fall off of map, your induction system is not flowing enough air.

[5FDP]

The tune is too fat if you ask me. 11.48 AFR is way fat on the NA motor and then at 3,600-4,800 it goes even richer, stupid rich. 10.72 commanded is super duper fat. No data with a wideband to confirm that though. Hopefully you aren't masking a un-tuned airflow model by whacking it with a bunch of fuel to get a desired air fuel ratio.

Less fuel and slightly more aggressive timing seems like it would add power. Also dial the VE and MAF in with a wideband, the VE seems untouched.