The idea that Toyota, with all their resources, couldn't possibly conceivably produce their own engine for this car without it being utterly cost-prohibitive makes me shake my head. So much I get dizzy.
Was it easier to do it this way? Absolutely. Was it the only realistic way to make it happen? I aint buyin' that one.
And they could easily have dropped versions of that I6 into future versions of other Lexus and Toyota models.
Yup. Again, I get that it's easier and cheaper this way. But if you're trying to tell me it would be otherwise fiscally impossible for Toyota - second largest car manufacturer in the world - to offer a performance rwd sports coupe using their own proprietary chassis and engine, I'm going to ask what kind of magic wand Ford, Chevy, Nissan and Mazda are using.
None of those companies are selling cars that are all that comparable to the Supra, and have engines that are sold in other products.
And nobody passed a law that says that if they produced an engine for the Supra, it could only and forever be exclusively used in the Supra. And yeah, I guess front engine rwd sport coupes aren't all that comparable to the Supra. Well, none of them are cynical re-skinned BMWs, so you've got me there.
I can spell it out for you if you like.
The Miata is a lower cost car that sells in relatively high numbers. It's been sold consistently for 30 years. As a smaller company, the Miata is more important to the Mazda brand than the Supra is to Toyota. Plus it uses an engine that is used in economy cars which certainly helps keep costs down.
The Corvette is an iconic car that's been on the market for ~65 years. It has wide appeal being available with a manual or automatic, coupe or convertible, and in four levels of power. It's also generally more expensive. It shares its engine with the Camaro, and the same basic design is also used for a bunch of trucks.
Ford, basically the same thing as with GM.
The three above are basically the market stalwarts of lower priced sports cars.
The Supra, on the other hand, hasn't been sold here in 20 years. Over the generations its mission hasn't been consistent. It competes in a fickle market that is much smaller than it used to be. This car is a gamble by Toyota. It could be quite successful but maybe it won't be. It's not a halo car for the brand the way the other cars above are.
There's no doubt that Toyota could create an all-new engine for the Supra and it could have other applications. But like I said, it also needs an appropriate platform, which at this point it doesn't have. It's unlikely that such a platform would have any other applications, unless you wanted to build a Lexus variant but that doesn't really seem to jive with the Lexus mission (the LC500 seems like a more appropriate offering). So if they're going to go with a third party platform, it doesn't make any sense to design an engine that works with that platform but possibly doesn't work with your own products.