I second the referral to the GG. It's the best place to get info on all
things Grumman. The group's very friendly, responsive and some very
knowledgeable folks including David Fletcher and Cliff Hanson reply with
regularity.

As to cooling, I swapped out the oil cooler for a bigger one with some
positive results and rebuilt the baffling on my Tiger. As part of a
pre-buy, I'd definitely have someone who knows what they're doing look at
the baffling. If you're planning on doing the HC upgrade, why not look for
a Tiger instead? I didn't price Cheetah's so don't know what the price diff
is.
In any event, you'll love the airplane....
As with all recommendations and comments....you got what you paid for!
--
Patrick Flynn
Sammamish, WA
79 Tiger N4543A KRNT

"Sydney Hoeltzli" wrote in message
...
Duane MacInnis wrote:
Hello all,

I may soon be the happy owner of a 78 Cheetah.

I would be tempted to immediately install the LoPresti cowl & rudder
cap,
and the Powerflow exhaust.

When the engine croaks I will go for the 160 STC, but in the meantime
the
cowl and exhaust combination may extend the cylinder life on these
notoriously hot engines, as well as reportedly yielding some pretty
impressive speed increases and reduction in fuel consumption.

Any experience out there you would like to share?

Duane, you might want to join the Grumman Gang email list
(http://www.grumman.net) and put your question there. I'm not a
Cheetah owner, but a few points. First, the Tiger is a notoriously
hot installation. To my knowledge, Cheetahs aren't particularly
under-cooled and don't have a particular problem with valve wear
or cylinder life. If you have good cylinders to start with, they
should last fine.

Second, I think the general opinion is the best thing you can
do for a Cheetah is top it and do the 160 HP STC. One of the worst
limitations in the Cheetah is poor rate of climb (esp. at high
density altitude), and the word from those who've done it is the
160 HP conversion really really helps out. You won't gain speed
but you'll chew your knuckles less on short-field takeoffs in
summer so you'll definately gain utility.

I don't know what the real-life speed increase from the tuned
exhaust is. I don't know anyone who's done it. The skinny at
last year's convention is that several people had volunteered
a test-bed to produce systematic numbers and the company was
uninterested. Make of that what you will. Ask on the Grumman
Gang if anyone has done it and what they saw IRL

I don't think LoPresti even markets the cowl as producing a
speed increase for the Grummans. From those I know who've done it,
either it doesn't add much or, they did a whole bunch of other mods
at the same time (new paint, fairings etc) so it's problematic to
say which did what. JMO, but I don't think you're going to turn
your Cheetah into a Tiger by throwing a lot of money into a tuned
exhaust and a LoPresti cowl. If you have a Tiger and you're getting
a paint job I think it might be worth the money for the improved
cooling.

If it were my money I'd spend it on the 160 HP mod ASAP.

Without any mods, you'll still be nipping at the tailfins of
Archers and pulling away from 150 hp C172s. Don't be greedy *g*.

FWIW,
Sydney (Grumman AA5B "Tigger")