Quote:
Originally Posted by Frank Lee
I don't think the non-Yunick cams were Miller cycle.
They were probably just like any of the "RV" or torque cams, intended to move the torque band down low.
I had one of those in a 283 in my '74 Nova; IIRC I usually got 23-24mpg with it when I behaved myself.
25mpg is a hella long way from 30 though.
|
Definately not. That's one thing i'm sure of. They dont run 14:1 compression on 87 octane.
The Miller/Atkinson cycle data sounds about right. What i'm wondering is whether that technology, for a given amount of fuel and air, is more efficient than a small engine without it though. (if it isn't then it's kind of silly...)
The Yunick stuff is completely different, that was just another "lost to history" story to share.
As to the Vicky axle ratio it was somewhere in the 3's I think, cruise RPM on highway was like 2400 maybe, somewhere in the mid 2xxx. There was no overdrive or lockup. Definately no 2 speed axle in it or other tricks. The only trick was a switch pitch converter that I remember - stalling at either 1800rpm or 3200rpm, the latter would get out of the sub-2500rpm 'hole' giving more torque to get off the line decently. The former used once you were at cruising speed.
As to why hunt it down vs a diesel... why not? Other good mileage enhancing ideas have been lost by the wayside (does anyone remember the "6 cycle" engine described in Mother Earth News in the 1970's that almost doubled power or mileage, your choice, by having two power strokes? No? Thats why I bring up these topics. Nobody is using that either that I know of.) and some for pretty poor reasons. It's either worth bringing back to life or worth verifying as researched and disregarded for the right reasons.