Any Early LS1 Corvette People Confirm This?

[cmitchell17]

I was reading a article on the development of the C5, LS1, and LS6. Apparently the C5 Chief Engineer stated that in 1997 they changed the calibration to basically stay in closed loop even during power enrichment and WOT. Apparently he said they did this by going "slightly rich of stoic"?

I've looked through all the early LS1 PCM files I can find and I don't see any evidence of this statement being true, but I find the source creditable:

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I personally am I big fan of tuning using the stock O2 sensors at WOT by forcing the tune to run stoich all the time. I know people have it drilled into their heads that if you run stoich at WOT for even just a second your motor is going to blow up. I haven't done the math to calculate the extra heat capacity provided by the extra ~15% fuel at WOT/PE. However just guestimating I bet its only about probably 1 hp, but nevertheless would be a very interesting calculation to do and shouldn't be that involved.

[zl1killer]

have you ever logged your car(s) or others and recorded the fuel system status under normal driving and WOT conditions? WOT the computer goes straight off the mass air flow sensor and reads the air coming to the engine. You can take a factory car and simply increase or decrease the MAF table curve up or down and net a fueling change. Its not exactly the correct way to skin a cat though. You know how sometimes what is written or published is slightly changed or misunderstood, or the meaning is lost from what is truly in the words that were stated by the person? I have a feeling that may be the case.

[Ben Charles]

That engineer wasn’t the program engineer I assure you.. 97 still does open loop

[2xLS1]

He is wrong about the injector sizes on LS1's too.

[cmitchell17]

My thinking that it could be pre production? We know there were a lot of GEN III truck applications that run stoich at WOT, but this is just because they have a PE delay mode, not necessarily that they are trying to run stoic at WOT.

I was also interested in the fact of how he explained "we run just rich of stoic" like he was trying to describe that you can get interpretable readings from the narrowbands as along as your only slightly rich.

I am just really unimpressed by how the supposed "Chief" engineer dosen't realize what the programmers did, but I mean I get it, I am a engineer on the mechanical side and if I wasn't friends with the electronics and software guys I would be clueless as to some of the stuff they are doing that will probably matter for my application.

[cmitchell17]

Yeah I understand that, but I was getting more at the fact how they are saying they basically run a stoich mixture during their supposed "power enrichment".