Many overhaul firms do not refurbish parts in-house but ship parts to
machine shops, like Aircraft Specialties, for rework.

Aircraft Specialties will custom balance parts for any customer, upon
request. Key word there, upon request. The extra cost is only 100-200
bucks, but if the customer doesn't request it, then the factory tolerances
are allowed. And factory tolerance is wide.

The two major actions that will contribute to smooth running engines. is
balance of rotating/reciprocating parts plus a matching, a 'balance', of
cylinders.
A lycoming or continental is just a number of single cylinder engines
grouped together. If one cylinder casting is so many 'CC's' different, it
only stands to reason that the combustion power will be different.

Supposely, since I've been informed but I haven't flow benched them myself,
the investment cast superior cylinders flow within 2% each. Much better
than the 15-17% difference of the old Lyc cylinders of the 1980's era.


good luck
Kent Felkins








"Roy Page" wrote in message
ink.net...
The Lycoming 0-360 A4M in our Archer is now 2250 SMOH and we are intending
to fit an exchange overhauled engine very soon.

The decision to pull the engine out was easy compared with trying to
decide on the engine to buy.
We have a number of quotes and researched factory and field overhaul
options.
Our list of choices has been narrowed down to the following all of which
are overhauled to new limits and fits.

1. Signature Engines - With new Millennium standard cast cylinders.
2. Penn Yan - With Penn Yan overhauled cylinders.
3. Penn Yan - With new Lycoming Cylinders.
4. Penn Yan - Millennium Certified Overhauled Engine
5. Lycoming factory overhaul with new cylinders.

The above engine options are listed from lowest to the highest price.
The prices range from $14,000 to $20,000.

In another recent posting somebody else commented:-
"If you paid out a lot of bucks for a new aircraft you would be sitting
behind a new Lycoming so why go anywhere else ?"
And indeed why would you go to anybody other than Lycoming, but the
dollars are very different !

A smooth running engine is very important and we will fit a new prop at
the same time.
As far as I have determined only the Millennium Certified engine has parts
balanced to published specified weight tolerances.

So help me make up my mind which engine I should go for because the
potential dollar savings are distracting me.

Thanks,

--
Roy - N5804F Piper Archer
"I have had some bad landings but I have never missed the runway .....
yet"