Show Less Responsive To Heat Iol Nearly automobile showrooms showrooms showrooms show show- rooms thru throughout hout the country have echoed the Ilu question stion What is an in in in- var ar strut piston the piston the the new type in in- ro ro in the Bigger and Better Chevrolet on January 1 O. O f E. E Hunt chief thief engineer of the Chevrolet Motor Company attempted here today to answer this question for the thousand thousands ands and of or people who have seen the new ear car and aDd asked about this outstanding feature Inver according to Mr Hunt is a construction of the word invariable Jt It is ia the name coined to describe the octal used in making the piston strut which is cast as an integral part part-of of the piston just above the pin bole and aDd has bas its ends firmly embedded ed d in the metal forming the piston lac lace Mr Ur Hunt explained is less responsive 3 t to h heat at or cold than any other ether metal known It is a special nickel mckel steel teel alloy of extreme toughness toughness tough tough- ness 11 and rigidity and is practically the same Ame metal as that used by the United States Stales Bureau Dureau of Standards to construct its In and in the manufacture of precision Instrument A J light h alloy piston expands when heated which means that unless this expansion i is properly controlled ex ex- artus ve clearance must be Bellowed allowed between the pia piston ton and cylinder walls to to prevent tut sticking and scoring resulting re- re lg in piston slaps laps and oil on pumping This control is effected in inthe inthe the Chevrolet olet piston by use use se of the wh which permits ts a B clearance of only inches between the piston i and nd the cylinder wall as compared to and in clearance with a piston that has no 10 0 oiled ex ex- |