Remember that twin-turbo, 4.2/5.5-liter LT V8 we mentioned earlier? Well, if not, head on over to our latest article on it and check out the details. But to bring you up to speed, a financial document—that was later forcibly taken off of Corvette Forum— leaked several months back and it had some pretty juicy info in it. The document showed that GM planned to produce both a 5.5- and 4.2-liter, dual-overhead cam V8 in the coming years, alongside the current LT5 powerplant.
After that tasty tidbit of info, we gleaned yet another look at what appeared to be a twin-turbo, dual-overhead cam V8, that we assumed would either be the 5.5 or 4.2-liter mill, in a set of CAD renderings labeled “LT7.” This led to the belief that the Gen VI LT was on its way and would be ditching the cam-in-block design of its predecessors. But whether or not it was the 5.5-liter or 4.2-liter we were getting a look at was, and still is, undetermined—though it clearly incorporates many of Cadillac’s turbocharging technologies.
All of this was substantiated by GM’s hurried attempts to have the renderings and documents taken down under the threat of litigation. And now we find out that the LT7 just may be destined for a Cadillac, not a Corvette…maybe. Back in 2016, Car and Driver picked Cadillac President Johan de Nysschen’s brain about the future of Cadillac V8s, and he was pretty forthcoming about what the future held for the marque.
de Nysschen mentioned that a twin-turbo 4.2-liter V8 was on its way and would likely power the next generation of CT6. He even went as far as to say that the engine will make “in the upper 400s” when it comes to power production. It would make sense that a few of the scraps of gossip we’ve been getting over the last few months could be the development of Cadillac’s new flagship engine—not necessarily the Corvette’s.
However, we do know that a 5.5-liter V8 is still unaccounted for and could be the engine seen in the CAD drawings of what is likely the C8 Corvette. While the LT7 is almost assuredly heading to the mid-engine Corvette, it piques our interest as to what they are doing with the 4.2-liter V8. While they’ve said it will power the CT6—which makes sense since Cadillac has already announced that they will drop the CTS and ATS from the lineup at the end of 2019—that doesn’t mean they don’t have their own halo variant of the C8 Corvette on the way.
The CAD drawing of the LT7 in the C8 Corvette uses many features of Cadillac’s turbo tech, including what appears to be exhaust manifolds cast directly into the heads, among others. It also wouldn’t be the first time that the Corvette’s architecture was nabbed and used for a production Cadillac (remember the XLR?).
But regardless of whether we get two supercars or just one, we are likely getting two new V8s from the General and that’s something to be stoked for. It’s an exciting time to be a GM fan and the internal combustion hasn’t yet reached its zenith, even with electrification on the horizon.