Quote:
Originally Posted by Steve Carlton
Interesting info, Sammy. What's your opinion of I5s and a 60-degree V8 (Yamaha built for Volvo)?
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i wuz typing part of that answer before you axed it.
As fer 60 degree V's, it's all about packaging. Making it smaller so it'll fit.
IOW compromize.
Is a 90 degree a better design? Yes. Can a 60 degree work? Yes. But it has inherent challenges that must be addressed to keep the engine alive and reliable for a long time.
What's the smoothest engine that comes to mind? Ferrari flat 12. Naturally balanced, almost no additional metal required.
The Porsche 917 flat 12 was a compromize and acted more like a flat V8 than a true opposed boxer so it weren't as good as ferrari's version.
V-12s are also pretty darned smooth too without a whole bunch of extra rotational mass.
(extra rotational mass = less HP).
The porsche flat 6 is smoooooth but really long due to the independant throws and extra mains. But it has a minimal amount of counterweight which is always gud.
I also like the straight 6 like in the datsun Z cars and the beemers. They seem to run OK but take up more room and need a long-snout on the car.
The more counterweight you have to add, the more dampening, the more rotational mass needed to counter-act forces due to design configuration, the worse the design is and the more that can GO WRONG. IMHO of course.
Did I mention I have a certificate from Schenck Trebel for "Balancing theory and Applications" and another from Emerson/CSI for "Field balancing applications using the CSI 2130"?
I also have a Schenck Trebel balancing machine in my shop capable of hitting a tolerance of W2/N in many cases which is tighter than required on nuke subs. We can hit W4/N all the time.
Darn thing cost $60k.