Originally Posted by VinceTrifecta
Hi all,
This is a very good thread here. I don't get a chance to spend much time on the forums, but it was suggested I come here and post up.
We are a custom tuning company, we specialize in analyzing a customer's vehicle for inefficiencies, then make incremental adjustments to the tune until our analysis concludes the vehicle is optimally tuned.
The first 2010 LLT car we did produced a gain of 23HP and around 17TQ on the dyno, and I'll post the dyno sheet if I can find it. The reason it gained this much power was because the equipment that had been installed by the owner caused the WOT fuel mixture to be incorrect (very lean).
We've since tuned three of these cars - two "beta testers", and one "production car". We're in the process of also tuning a twin-turbo'd 2010 V6 Camaro (which is going very well).
The two beta testers' cars ended up accepting very few tuning changes. Despite the modifications, the vehicles showed a very decent air to fuel ratio, so there wasn't much to do there. The dyno car was way too lean, and the production customer's vehicle was drowning in fuel at WOT due to his modifications, to the point of misfiring which has been resolved.
As for timing, GM basically throws a bunch of timing at these engines, and lets the knock sensors pull it back out to adapt to the fuel quality. Our dyno car showed a solid 9* of knock retard (KR) on the dyno with the stock tune. Obviously we're not going to get any more timing into the engine, but we did experiment with WOT air to fuel ratio to see if we could reduce the KR with more (or less) fuel, and we also tried removing timing from the base timing table.
For cam phasing, we tried modifying these tables also, but we did not see any substantial changes in power, but did verify the cam phase changed via data logging.
So, we've proven the ability to change the cam phasing, timing, air/fuel ratio, DTCs, and torque management settings - all the things necessary to provide custom tuning.
I'll be the first to say this is not going to be a mass-market tune for stock vehicles, though, since GM tuned these so well from the factory. It only makes sense if the vehicle has a modification that skews the tune. It's not that it isn't understood how to tune them, only that GM didn't leave us much room for improvement. One area I'd like to delve into is the knock detection logic, but unlike other tuners that sacrifice engine safety for dyno numbers, I'm not real excited about reducing the knock detection factors - this is an area I trust the factory in.
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