SHORT-BLOCK BUILDWe torqued the crankshaft by first securing the bolts with a
speed handle, then torqued them all to 35 lb-ft, and finally to
70 lb-ft. Then we rechecked them all again.We checked the endplay of the crankshaft by placing a mi-
crometer in line with the crankshaft movement and carefully
using a screwdriver to snap it front-to-back. Our endplay
was 0.004 inch, just about perfect. A range of 0.003-0.005
inch is fine.The K1 connecting
rods are a thing
of beauty with
their shot-peened
exterior for added
durability. The
high-strength ARP
bolts thread into
bosses within the
rod structure, elimi-
nating the need for
rod nuts. We also
ordered up a set
of rod bearing by
Clevite, a division of
Mahle Aftermarket.The JE Pistons wristpins fit through the piston bore and
hold the connecting rods in place. It is critical to make sure
that the rod/piston combination for the bore you are filling
is correct with regards to the valve reliefs in the deck of the
pistons and the chamfer on the connecting rod, where it at-
taches to the crank journal. The chamfer must face outward
rather that against the connecting rod it shares the crank-
shaft journal with.
Twin spiro-
locks are
used on either
end of the
full-floating
piston wrist-
pins.To work on the piston/rod assembly, you must correctly
protect the sides of the connecting rods from the jaws
of the vice; these protective covers are designed to do
exactly that.13 161417151820 OCTOBER 2019 WWW.MUSTANG-360.COM
the pistons and also the piston skirt
pressures on the cylinder walls. In
worst, these issues can manifest as
increased internal engine vibration
and higher piston skirt wear, increasing
oil and coolant temps. On the positive
side, the shorter connecting rod length
(lower ratio) allows for shorter, lighter
engine combinations and engines
that will generate more vacuum at
lower rpm for better throttle response(increased timing advance) and low-
end torque.
In contrast, with a longer rod (and
higher rod/stroke ratio) the piston
dwells at top dead center (TDC)
slightly longer for more efficient
and thorough combustion, which
equates to slightly more power. As a
rule, engines with longer connecting
rods generate slightly more power
in the middle to upper engine rpmrange. These engines have lower
intake vacuum for reduced rpm and
torque, making this system the better
choice for racing engines than street
engines.Parts Is Parts
Most things are the sum of their
parts, and with this engine build, that
adage was never more accurate. The
parts list for the short-block portion of