How Do Piston Expanders Work?

[JerseyHarold]

I found a box of Thexton piston expanders while going through a box of stuff in the garage.  Never heard of them.  What is their purpose?  Any enlightenment appreciated!

 

Harold

[Don Coatney]

Piston expanders or piston ring expanders?

 

 

[JerseyHarold]

Piston expanders.  They're small U-shaped pieces of steel.  I'll put up a picture later.

 

EDIT:  I did some online browsing and found the attached patent:

 

http://www.freepatentsonline.com/2442834.pdf

 

From what I read, the expander reduces piston slap and decreases bore wear, which (I guess) reduces the need for re-boring.  Interesting.

Edited June 30, 2019 by JerseyHarold

[Plymouthy Adams]

 

read the instruction sheet....these are only for x style piston and yes should control piston slap

[JerseyHarold]

I'd bet GM could have solved their piston-slap issues with a set of these babies....

 

These are the Thexton version....

[kencombs]

I've seen the expanders before, but never the instructions on retempering the pistons! 

[Andydodge]

I suppose these piston expanders would work the same way the Charles Atlas adverts worked in stopping sand getting kicked in my face..........lol........Andyd 

[MackTheFinger]

Those look like something from a Warshawsky or JC Whitney catalog, right next to the water injection setup.  ?

[greg g]

But our pistons are oval ground tomaloow for expansion, if you put these in the oval becomes round, what happens when the get hot???