XXXX.

[Air Ministry .]

Bear with me !

this is a 1 - 1/8 enlargement ( 125% area ) of the .40 / .46 one . of something I dreamed up in 76 .

[Air Ministry .]

Drawing the bulkheads ( formers ) to 4 AM , today I was a bit muleish , to fit the engine in from the Top & bolt Down onto the Bearers ,
The Case needs cleaning up . As its Chinese , its a case of w.t.f. not .

The original 51 thing is from the old .49 carved into the case mould. So is Supurflous . 

[Air Ministry .]

After carving the lumps of the Bypass of the .51 case , With great foresight I thought Id better put something to identify the displacement for future generations .
After some contemplation it was Evident V. ( five ) I. ( one ) for our Roman Fiends as numbers are to tricky to scratch !

Then proceeded to ' relieve ' the GS 40 of its excess Bypass Material - down to 16.5 mm from C/L for those who wish to Emulate .
Still gives a good clunk when tapped with a File . 

Much conjatation prevailed untill the Obvious flashed into ones conciousness . X ( ten) x four . Being in Australia . ! 

[Air Ministry .]

Carving that thing off on the 51 lets you get a screwdiver on the bolts unimpeded. 

[EddyR]

Matt     I have a few of my early ST/G21 40's and 46 motors that I did a lot of case work on. Now I can't tell the .40's from the .46 motors unless I remove the head and measure them. A few guys changed the 46 number to a 40 back in the day so they could run .015 lines.
Ed

[FLOYD CARTER]

A little filing on the case can't really improve the weight that much.  The real weight reduction comes from:

1)  throw away the stock muffler

2)  grind metal off the cylinder head (although I haven't yet done that)

My ST51 came from Tommie Lay, so maybe I should leave it alone?

Floyd

[Air Ministry .]

Floyd , Ive done it so I can mount them Team Race style . Thou I drop it down then slide it forward .
With all the lumps on the side itd fall down crocked & jam .
Runs ive had with the Std. Italian ones ideally suited to the aeroplane , though the .40s back up
for if theres a cyclone as the 51 sounds a bit odd on a 10 x 4 . ( detonation actually ) .
Though I think a ABC G 45 would be a better bet - Ive got a chinese . 40 so dont see any great tradgedy in customiseing it .