[DGthe3]

The Gen III/Gen IV aka 'LS Series' is coming to an end soon. They are being replaced by the Gen V, which is said to be known as the 'LT Series'.

We have few hard facts, but from the sounds of things the engines will be all aluminum (including the truck engines), feature direct injection, and variable valve timing. Active Fuel Management will likely stick around and be improved upon. Additionally, its expected that they'll rev a bit higher than the LS engines typically did.

I would assume that the compression ratio is going up because you can use direct injection to cool the air charge, which then reduces the chance of pre-ignition. You can also use it to inject fuel just prior to when its supposed to ignite, eliminating the chance of preignition, but I don't think automakers are doing that just yet. Anyway, look at the V6 in the Camaro. It has an 11.5:1 CR and is tuned to run on regular, compared to the 10.7:1 for the LS3 (10.4 in the L99) which recommends premium. Imagine what they could bump it up to for an engine that is supposed to run on premium ...