Boost By Pass Mod

Photo and Instructions by Andy Whittle

The Lightning motor  has a valve on the near the back of the blower on the
drivers side that relieves or bypasses air past the blower. This valve
serves two purposes on the Lightning motor. During high vacuum situations
(when you are not requiring high power), air leaks around the blower to
avoid ware on the blower drive and heat. Once the motor gets to 0 vacuum on
it's way to boost, the valve is designed to close and allow the motor to
build boost. The other function that this valve is designed to do is protect
the motor from over-boost when the motor hits the rev limiter. The problem
is that when this boost bypass is energized, it remains in that position for
quite some period of time. This only seems to happen when doing tire warming
at the track and the first time you find out that the bypass is in 0 boost
mode is about 30 ft from the start line on your way to a 17sec @ 78 MPH
pass. This mod is the 10 min and $3 solution to this problem. Note: I have
heard that the boost bypass my come in with an over-heat situation and may
also come in with the torque reduction if still active in your chip.

Remove the pink line from the top of the boost control diaphragm valve, (not
the solenoid valve) and plug it. I used a 1/4" bolt cut to about 3/4 inch
long but that still has about 1/4" of smooth shank so you don't get an air
leak. You can use a 1/4" hose mender and a 1/4" cap.

Next, get 3/16" Tee at the auto parts store. Put this Tee into the boost
hose that goes into the firewall and up to the boost gauge(there is a white
3/16" hose mender in this location stock). Get 9" of 3/16" rubber fuel line
to go from this Tee to the top of the boost control valve.

The result is the computer will no longer have the ability to dump boost at
the shift (torque reduction) or as part of the over-rev protection. The
computer will never know and will not throw a soft or hard code. The boost
bypass will still be active at idle through near zero vacuum, and closed
shut in all boost conditions. Just be careful, The computer can't help
protect you from over-revving and over-boosting or over-heating and doing
damage to the motor.

see http://www.ncs-stl.com/Images/BoostMod.jpg for photos