Avanti Pistons!

[mfg]

A piston for a Studebaker Avanti R4 engine weighs more than a piston for an Avanti R3 engine......True?

[r1lark]

True, by a little over 3 oz. 

[Dwight FitzSimons]

The R4 piston is heavier because of the raised portion of the top of the piston (versus the R3 piston).  That reduces the combustion chamber volume, thus increasing the compression ratio from 9.75:1 to 12:1.

--Dwight

[mfg]

13 hours ago, r1lark said:

True, by a little over 3 oz. 

 

8 hours ago, Dwight FitzSimons said:

The R4 piston is heavier because of the raised portion of the top of the piston (versus the R3 piston).  That reduces the combustion chamber volume, thus increasing the compression ratio from 9.75:1 to 12:1.

--Dwight

True is CORRECT here! (and that sure is TALL compression!!)