Quote:
Originally Posted by Robert_K
Thanks! Yeah, surprised there isn't more tuning options for the VQ37.
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Because the VQ37 basically tunes itself, at least as long as the engine is within the ballpark of an NA stock block + heads. The stock ECU dynamically determines timing via feedback from a very sensitive knock detector (it will advance itself until just under the threshold of knock, or retard itself if knock appears), and has 2x wideband O2's + 2x MAFs running in realtime for self-regulation of A:F.
Really all there is for the tuner to do via UpRev for power is (1) Precisely calibrate the MAF voltage tables with a known-good high precision O2 sensor, because the MAF units have manufacturing variance and the stock voltage tables are only an approximation, and (2) Set custom A:F targets in a table based on RPM and fueling input. Given appropriately-calibrated MAF voltage tables the A:F values here are going to be followed very literally, so the only tradeoff here is that if you go a little *too* lean to try to pick up power, the ECU's going to back off your timing advance automatically to compensate for the slightly increased knock, which may come out worse than leaving it richer in the first place.
For boosted applications it becomes more necessary to screw with the K-fuel multiplier to get everything scaling in the correct range, and to set spark advance to a reasonable starting point so that the ECU doesn't have to learn the correct values "the hard way" via excessive boosted knock. But still, I think the bottom line is we don't see much ECU work for the VQ37 because the cases where it really matters are fewer than on past engines.