Swain coating piston skirts

Jay Whitely jwhitely2000@yahoo.com
Thu, 26 Dec 2002 19:38:47 -0600


Hey guys,

Let's say you were to Swain coat your piston skirts
for a turbo motor. In my case, I am coating the skirts
of my stock 86mm GTi-R pistons. According to Dan
Swain, the coating adds 0.0015" to 0.0020" to the
diameter of the piston.  I will then get my cylinder
walls torque plate honed to match the new size of the
pistons.  Here is where my concern lies:

The diameter of the bore will increase by about
0.0020".  To figure out how much the bore
circumference increases, multiply by pi (3.141592654).

This equals 0.0063".  So, the bore circumference will
increase by 0.0063".  This also means that my ring end
gap will now start out 0.0063" wider as well.  I don't
have my FSM handy right now....is there enough range
in acceptable ring end gaps to cover this 0.006"
variance?

Thanks for the advice,

=====
Jay Whitely
Tampa, FL
1996 200SX SE-R
GTi-R powered, F-MAX Stage 2