Jim McKown’s 1977 Chevy pickup came
to Street & Performance with the LS-1 in the bed. He wanted
the S&P installation team to
complete the install with all the necessary
wiring and bracketry to make his truck into a fuel efficient,
high performance and dependable daily driver.
Jim wanted to update his ‘77 with
an LS-1 to have the fuel efficiency, performance and
dependability that the LS-1 offers. These engines are readily
available in salvage from the ‘98-’02 IROC/TA and
the ‘99 up 4.8 - 5.3 - 6.0 small blocks or the 8.1 big
block from trucks. The 6.0 and the 8.1 are not as fuel
efficient but are better suited for towing due to the torque
that these two engines develop.
When getting an engine from salvage, be
sure to get the computer, mass air flow and all oxygen
sensors.
Jim delivered the ‘77 to Street
& Performance with the used 5.7 IROC engine and 4L60E
transmission that he found at his local salvage yard.
Larry Harrison installs the S&P
engine motor mount adapter plates to the LS-1, which
positions the factory engine mounts to the correct frame
location
The factory mounts are then bolted to the
S&P adapter plates. S&P recommends the use of
anti-seize compound on all bolt threads.
Jim wanted to use the factory exhaust
manifolds. The drivers side manifold had ample room, the
passenger side had to have some of the manifold ground away.
S&P provides headers for this
application.
With the engine setting on the front
mounts, the factory LS-1 alternator and P/S cleared the frame
rails, but the factory LS-1 air compressor had to be removed
and will be relocated.
The rear cross member was moved forward
using a GM rubber transmission mount.
Mounting the S&P upper passenger side
AC bracket and idler kit to install the Sanden 508 compressor.
The compressor was then mounted to the
bracket using a Good Year Gatorback belt #4060970 which is 97
inches long.
Jim wanted to use Datoka Digital
instruments which requires relocating the coolant temp sensor
from the head due to the heat from the exhaust manifold.
To accomplish this, you can drill the top of the water pump
outlet boss and tap to the size that is required for your
sending unit. The use of wheel bearing grease on the drill bit
and tap will help to keep the shavings from falling into the
water pump.
Larry installed the Dakota Digital
instrument
cluster into the ‘77 dash.
The cross flow radiator has the inlet on
the top
passenger side and the outlet on the
lower
passenger side. The transmission cooler
is in the driver side tank.
The ‘77 cross flow aluminum
radiator was ordered with dual electric fans from Griffin.
The Griffin radiator came with a
provision for the steam line that comes off the cylinder heads.
The lower hose is a Goodyear # 60867 and the upper hose
is a Goodyear # 61331
The colum shift turbo 400 transmission
linkage was adjusted to the 4L60E transmission, however this
will not allow the driver to force the transmission into first
gear.
16mm O-ring to AN6 adaptor fitting was
used to connect the presure side of the factory power steering
pump to the gear box with Aero-Quip hose.
The gear box uses a 18mm O-Ring to a male
AN6 adaptor fitting to attach the pressure hose.