The v6 is the same 11.5:1 CR as the LT1. It also is a high revving DOHC engine that redlines higher than the LT1. Engineers designed it to be a high performance engine and to run 0n 93 octane. In fact any tuner can verify there are two Octane tables in the tune same as the LT1, and nearly identical in ignition timing advance.
The Marketing department made the choice to state 87 to appeal to the economy minded demographic that likes the styling but want an engine option for 87 octane. Just as GM stated Dexos1 (early version) that was a cheap blend, not a full synthetic and caused all the premature wear and damage on these to appeal as well when NO GDI engine should run a blend. They can't deal with the greatly increased raw fuel dilution, 8-12 times that of the old PI engines they replaced and just the past few years changed Dexos1 to a full synthetic, but the ESP formulation Dexos2 is what should be used in these as it combats LSPI so provides protection against piston breakage.
Tuners have been sharing dynos showing the gains running 93 for years with these, but the problem is those that do try it put in maybe a tank and as it takes good deal of driving before the ECU will default to the high octane tables and don't notice as it can take a few tank full's and they simply conclude "it felt no different".
wintertopdown and lt4camaro are both 100% correct. The engine in everyway is designed as a high performance engine even more so than the LT1. Compare the stock HP per liter with the LT1.
So the Engineers did an awesome job (Opel and more use these same engines) designing these, but GM playing games for marketing purposes have left power and longevity on the table to appeal to the target demographic. As all automakers do.
As the decades progressed from the days where the owners manual was your bible to care for the engine and get long life and few problems they have transitioned to a blend of accurate info and half truths to fit both legal departments, regulatory (CAFE fuel economy standards, emissions, etc. directives and marketing. Automakers have this down to a science.
These are not the low compression engines of old.
Cheers!
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