Hey guys - I'm looking to see if I can get a little direction from the experts so I can get on track with the Calc.VET Tuning method.

I have a 411 PCM on a 355 SBC through an EFI Connection kit. Engine has about 11:1 compression, GM Fast Burn Heads, TPIS MiniRam, 224/230 110 cam, headers no cats. Car is 89 Corvette with 6 speed and 3.92 gear. Injectors are 32 lbs. @ 43.5 and I'm running 44 psi without a vacuum pull on regulator. I'm certain that my harness is correct and my spark settings are modified properly, so I do not believe I have a hardware issue. Also, the engine has less than 10,000 miles on it and has 185 psi on every cylinder +/- 5.

Current tuning setup includes FAST WB with analog input. It reads extremely lean in most light acceleration and steady cruise situations 15 - 17, while the LTFTs are negative 11 to 18. With any quick tip in or heavy load/throttle the AFR goes way rich usually 11.2 avg., sometimes 10s. This causes the car to shudder and even give me a blinking MIL. The only thing that seems to be almost usable is the idle at 14.3 - 14.5 on the WB. With the camshaft size, I'm definitely getting reversion but I have double checked the WB with a new AFX / NGK setup and found similar results, so regardless of overall accuracy of the FAST WB, it seems to be correct.

These issues seem to cause drastic spikes and holes in my Maps when trying to perform Calc.VET. I can literally have two cells next to one another at the same RPM where one goes up and the next goes down dramatically, and the cell count is high on both. I smooth the table manually, run it again and get the same results. I cannot seem to get anywhere with tuning my Main VE Table and MAF.

Given I'm running an SBC with fair duration I'm certain that the injector timing is way off but I'm not quite sure what to do about it because I cannot seem to measure any changes that I have made to injector timing.

Can I get some of you guys to possibly give my tune a look and make some suggestions that I can try changing to settings where my AFR can come more in line? I'm feeling pretty helpless with this...

I have purchased an AEM 30-0333 with new 4.9 sensor so I can hook up Serial, but given that I have corroborated my current readings with another known working sensor I'm reluctant to install it until I get the tune more reasonable where I don't shorten the life of the new sensor.



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