Posted for daniel newland <compositeguy@sbcglobal.net>:

 Hey, many of you guys have a lot more experience than I do on turbines so
feel free to object here (as if I could stop you!)  I first looked at the
Innodyn at the 2004 OSH show and it looked pretty neat!  They did not have the
twin pack, just the single version with one rated to 255 HP for a weight of
180 lbs.  The claimed fuel burn was 14 GPH at that HP.  To my way of thinking,
if I were to replace my IO 550 I planned in my ES with this, it would solve
the forward CG problem (or potential problem), increase by 300 lbs or so my
payload capacity and above 3000' or so deliver the same performance as the IO
550 but get better as we went up.  And if you were to realize an honest 300 lb
weight saving, I would guess that your climb wouldn't be any less than the 310
HP Continental.
 
 So the twin pac may be great for the right person but to me, the 255 HP would
be right in between the IO 360 and IO 550 performance but have a lot more
weight to play with and better high altitude performance.  Since Innodyn
didn't have any real fuel burn and total output numbers at altitude, I don't
know what the real comparison would work out to as far as high altitude is
concerned but I am only guessing it should be pretty decent.  If that is truly
the case, then the single turbine 255HP would look really good on the front of
my ES.  Even if I were to fly slightly slower but have the extra payload
(maybe eatten into by a bit more tankage, granted), then it could still be a
very good deal and at about half the cost of an IO 550 (offset probably by the
difficulty of getting insurance).  And it would get around the problem of
dealing with whatever is going to become of 100 octane LL.  The low altitude
hops which I would expect to do a fair amount of might be the Achille's heel
 though.  Hamid had a great point in that perhaps the best speed mod is to add
more fuel storage capacity!
 
 That is my only slightly informed opinion.  Somebody out there can probably
cut that to shreds.  Any opinions?  What do you think of the Innodyn?  Is this
real or pretty hyped up figures that misses a lot of critical details?