Whoa there. Parent post is loaded with incorrect information:
I have never heard of a 90-degree V12. Most are at 60 degrees, with the notable exception of Ferrari's V12s (which have historically been at 65, or 180 in the case of the 365/512 engine series.)
A flat-plane crank V8 is essentially two inline-four engines. A cross-plane crank V8 uses an uneven firing order and is not the same.
With their crankshaft counterweights, cross-plane V8s have better dynamic balance than flat-crank V8s. There's a very good reason why flat-crank V8s aren't commonly used in road cars: unless you're able to make the engine internals very light, the noise/vibration/harshness (NVH) will be awful, and most consumers won't be interested in buying your car. The cross-crank V8 is not a "dirty kludge", and most people prefer the exhaust burble to the sharp bark of the flat-crank design.
Almost every major V8-making manufacturer produces exclusively cross-plane crank V8s. Ferrari, Lotus, and TVR are the only major exceptions. Saying that the only "real" V8 is a flat-crank is silly.