Early LT1 Power Steering Upgrades for Reliability at Higher RPM

>>LT1 P/S Failure Overview: The previous owner of my car
had 2 types of recurring, very frustrating failures of a ’93 LT1. This
resulted in DNF’s and mandatory trailering after about 12
of 24 road track
events. We battled these issues by installing
fresh factory and aftermarket
parts. This was fruitless.
Special SCCA Trans Am Team Racing adapters
with Custom
Earl’s connectors on braided lines also failed! After scratching
my head for 6 months, I finally found the correct fixes.

>>Problem #1:The longer
steel P/S
line that looks like a brake line goes from the right side of
the rack to the left side. It dances like a piano string at high RPM and
develops stress cracks at the ends when tracking these cars
see sustained
elevated RPM. We had 3 failures (one lasted just
2 track days)and it’s
a real SOB to replace.

>>Solution #1:Split
two 3” long pieces of thick
1/4” fuel line and slip them over the line.
You will notice
the fuel line will touch the rack housing. Wrap a couple
heavy
duty twist ties all the way around the housing and hose/line to
restrain it. No more vibration. >>Problem #2:The high pressure P/S hose
that enters the top of the pump is a faulty design. It
vibrates and cracks
at the fitting and it also places
tremendous vibration force on the tiny
o-ring that eventually
degrades and fails. I have seen both failure modes
(and so has
GM).

>>Solution #2: General
Motors made a ”secret”
2 step running change to the LT1 design to correct
this. No
recall or TSB was issued. This bulletproof ”secret” upgrade should
not be confused with the early ’93 o-ring recall that did
not fix these
problems.

Upgrade Step 1 was
they redesigned the hose to make it take a radically different
and longer
route to the rack. These revised hoses have an
extended steel line pipe
section about 8” long at the top
passing down along the idler pulley mount.
It takes a 90
degree turn under the pulley toward the passenger fender
and
changes to rubber and curls counterclockwise for about 270 degrees
actually protruding forward of the sway bar and then to the rack.

Upgrade Step 2 was
they added a drilled and
tapped P/S line restraint boss on the huge aluminum
accessory
bracket right behind the stationary idler pulley, so the line
can be held solidly to the motor assembly with a clamp and bolt. This
transfers vibration to the lower rubber section of the hose where it
belongs.
The later hose upgrade was a running change on some
late ’94 cars.

The new accessory
bracket debuted
sometime in ’95. To upgrade, you must buy the GM OEM ’96
hose and OEM ’96 bracket and retrofit. The correct hose is rare and
costs
$80 and some dealers will accidentally sell the early
hose to fit the
’95/’96 setup. Make absolutely sure the
’96 GM hose P/N is different than
the ’92-’94 GM hose
P/N. Many dealers do not recognize the revised hose
because
the earlier hose bolts right on any LT1 and it’s cheaper.

FYI, I have confirmed
the aftermarket does not
sell the correct later hose for ’96 cars. The
huge
accessory bracket is about $90 and takes a while to install. It’s
a good time to do Optispark mods or replace ignition wires.

Look at a ’96 LT1
or LT4 Vette with a
flashlight to see the difference in hoses & the accessory
bracket boss & restraint.