In Reply to: You're right, but I must disagree... posted by J.D. on October 24, 1999 at 22:21:06:
: You wrote: "Very few V6s are derived from V8s anymore, at least for automotive applications. The optimum angle for a V8 isn't the same as for a V6, which means when you make a V6 out of a V8, you either get a rough V6 or need to put in a balance shaft. Same thing works the other way--witness the balance-shaft equipped, V6 derived V8 in the most recent SHO Taurus."
: I understand that a 90 degree V-6 is far from the optimal configuration (60 degrees between the cylinders is the optimal config). In fact, numerous V-6s are derived from V-8s. Every GM designed V-6 with the exception of the 3.0 V-6 in the Catera is derived from some V-8. Ford has numerous V-8 derived engines also, as does Chrysler.
Actually, the Audi V-6 is a 90 degree unit. So are the new Mercedes V-6s. I'm sure the latter uses balance shafts, not sure about Audi. I test drove an A6 2.7T stick last week, and compared to the E46 328, that car raises quite a racket under brisk acceleration.
Honda's V-6 F1 Turbo 1.5, the one that won all those championships, was a 90-degree V-6. When they weighed the trade-offs, the lower center of gravity and more compact packaging of the 90-degree (you can put more things between the cyl banks) won over the inherently smoother operation of a 60-degree V angle.