New Cessna

What kind of performance increase would we see? Along similar lines would
these changes turn the 172RG into a real performer? (FYI: I love flying the
Cutlass).

Apropos of this (and I also love the Cutlass), I just got to spend some
time in a 172SP when the FBO's cutlass was unavailable. My experience
with 172s is that they are supposed to do 115-120 but don't always quite
match those performance figures. The Cutlass is supposed to do 135-140
knots, but this particular one has trouble doing 120 downhill, and this
tells me something isn't right anyway. That aside...

I thought the 172SP was "just another 172" with lawyer mods. But in
fact it does manage 140 knots on a good day, and 135 true on an ordinary
day. (Of course it probably helped that the aircraft was fairly new).
Seems to me that if they flipped the gear up they'd be able to tack on
another twenty knots, since that's what a (good) cutlass gains over a
172. Of course, maybe the extra twenty horses adds too.

Jose
--
Get high on gasoline: fly an airplane.
for Email, make the obvious change in the address.

Apropos of this (and I also love the Cutlass), I just got to spend some
time in a 172SP when the FBO's cutlass was unavailable. My experience
with 172s is that they are supposed to do 115-120 but don't always quite
match those performance figures.

C172 speeds are greatly dependent upon the prop pitch.
One of the four C172's in the flying club of which I am a member has a
cruise prop on it. At 2200 rpm it indicates 118 kts while a C172 with an
intermediate prop at 2200 rpm indicates 110 kts.
The slow accelleration of the cruise prop equipped aircraft is
noticeable on takeoff.

Seems to me that if they flipped the gear up they'd be able to tack on
another twenty knots, since that's what a (good) cutlass gains over a
172.

Sounds about right. However I doubt Cessna would build a new plane with
retracts for liability & maybe cost reasons. Cirrus and Lancair have
shown that FG can go fast if the airframe is slick enough. Maybe that
300hp Bombardier turbo V6 might end up in the new plane. That would be
quite a combination IMO.

Let's take a 172N, make it composite, same 160hp, no struts, flush antennae, with all the speed mods and a few other tweaks.

Hmmm... kinda sounds like a Cardinal : )