Did find three suppliers of 4 inch throttle bodies for the 20b.
These

are

105 mm each (4.17"). Accufab number AB-F105TBOR, Holley has three,
and
Edelbroke Universal racing #3877. The Accufab appears to be the
smallest
footprint and possibly the lightest. Or am I missing something?

Judging from a web search and until I can spend more time in the
salvage
yards, 105 mm throttle bodies were never stock on any engines. I
would

like

to be wrong and save that cash for other things.

Wade Bush
Flying 20b to be

They are simple to make Wade. Here is a nice large one made by Chuck
Dunlap. You could also weld it up from aluminum tubing and plate.
Most commercial ones are way more complicated than needed in our
application.

Paul Lamar

wadebush wrote:

I was thinking that way (making my own) but starting comparing
time-tools-experience-education-stock and pieces-plan/instructions
and then
decided to just buy one.  OK, I'll bite, does Chuck have more and how
much
for a four inch model?
Wade

Fred Vandeman wrote:

Others may also be interested, I certainly am.  If someone is thinking
about building one, maybe they could be talked into doing several.
Fred

The market is kind of small for 20B's TB castings. Ed Klepeis might be interested
in welding some up.

Paul Lamar

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