YvonC----It is an expression which refers to a piece of equipment actually operating very poorly compared to what is normally expected of it.

----- Original Message -----

From: Mark Steitle

To: Rotary motors in aircraft

Sent: Thursday, July 24, 2008 8:18 PM

Subject: [FlyRotary] Re: 13B--- N/A vs. Turbo engine buildup?

 

Paul,

I am running a N/A 20B-REW (twin turbo) rotary in my Lancair.  It has the stock 9.0 rotors.  I've read over and over that at the rpm range we operate, there is very little difference in power between low and high compression rotors.  I doubt that anyone that's ridden in my Lancair would say that it is a "dog".  However, I did do a little porting, so probably helps to offset the low compression rotors.  You can use high compression rotors, but you'll need to have it rebalanced.  I used the stock turbo rotors because I may want to turbo-charge later on and didn't want to tear the engine down again to change rotors. 

Mark

On Thu, Jul 24, 2008 at 5:20 PM, Paul Vermillion <paulo264@cox.net> wrote:

 

 

Subject: 13B--- N/A vs. Turbo engine buildup?

 

To Everyone—

                We have both a 13b  NA (unknown vintage—80's?) and a '91 Turbo 13B engine and are just beginning their teardowns, both allegedly running but internal condition unknown.   Would there be any problem running the Turbo engine (BUT NOT with the turbo setup-- AS IF it were a NA engine)?  Is it a "stronger" engine than the NA?  Would it need a different Timing setup?  Would there be a compression problem running it sans turbo? (Hearsay has it that it would be a "dog".)  If some of the individual parts spec out to be better in one engine but not in the other, would there be any problem/advantage in "mixing & matching" the various parts in the newly built up engine, i.e., rotaries, side plates, eccentric shaft, etc?   We would appreciate your inputs.    Thanks!

 

Paul & Don Vermillion