Slant six in a Miata ? Why ???

I agree. There is a cost savings when purchasing parts for these engines. That’s it! And not much ether! There not overly superior that it is a no brainer move to do. IMO, it’s just stupid. I’m also with you that if your doing the swap, it should be a good upgrade in power. This 170-/6 is not. Swapping in an LA or other American V8 would have been very cool.