flyrotary@lancaironline.net Mailing List Archive

Group,

Here are the important 20B Engine Model Codes in one post........Probably info to save

for those using or contemplating a 20B in their project...........Thanks Thomas

Kelly Troyer

From:	Thomas Giddings <tom@midwestaviation.net> Add to Contacts
To:	Rotary motors in aircraft <flyrotary@lancaironline.net>

FlyRotary] Re: Numbers?

Here is the second email I am quoting Brian Galloway>

"We find that the small dowel pin motors are weak. They crack sideplates easily when pushed past 10-12psi boost which is at around 530HP.

There is a fix for this. Cost about $2000.00 extra and the engine needs to be disassembled. We use the 12.7mm stud kit and bore and tap all the sidplates to accept the larger studs. Basically creating a girdle. The bock is bullet proof after this. We have one making over 1600HP at a little over 45psi boost pressure"

From:	Thomas Giddings <tom@midwestaviation.net> Add to Contacts
To:	Rotary motors in aircraft <flyrotary@lancaironline.net>

Here you go everyone: The engine should be stamped on all the rotor housings and sideplates. Look on the top of the rotor housings where is says "Mazda 20B"

Pre A code: 3 digit numbers only, no letter
A code : Letter A and 3 digit #
B code : Letter B and 3 digit #
All of the above are small dowel pin land motors

C code: letter C and 3 digit #
D code : letter D and 3 digit #

The C and D code have the upgraded sideplates, thicker dowel pin lands. Approx: 4mm thicker

On Mar 3, 2011, at 8:34 PM, Kelly Troyer wrote:

Thomas,

Share some of your new found info on the 20B with the group............

From: Thomas Giddings <tom@midwestaviation.net>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, March 3, 2011 5:23:15 PM
Subject: [FlyRotary] Re: Numbers?

Thanks Kelley....Your right...Brian knows his stuff...I have a very early 20B

Tom

On Mar 3, 2011, at 3:53 PM, Kelly Troyer wrote:

Thomas,

Try Brian Galloway in Calif.........He deals in Mazda parts and is very knowledgeable in

the 20B models and the differences between them.........Improvements were made in the

year models............For our use in aircraft the upgrades probably are not as important as

we are not severely stressing our engines like the racers (Auto) do.........I do know that the

later model 20B's sell at a premium...........The last time I corresponded with him he had

both early and late 20B's for sale............I bought a 20B auto trans bell housing from him

(My 13B "Cosmo" uses it between Tracy's RD1C and engine like "Bulent" of this group

.....See photo) attached)..........FWIW

Brian Galloway <ss427bb@hotmail.com>