Trying to help out a buddy with a LT1 'vette and
a cam in it, his idle is for **** and we think it's the
speed density (un)tune. Thinking I can cobble him
up a little "MAP bender" to fool the PCM into less
idle fuel by less idle MAP. But I have no info on the
MAP sensor characteristics, esp. voltage vs MAP
curve and any output drive / impedance info, for
LT1s.

Anybody got a handy link or scans / docs about
this stuff?

 

changing the map like that is going to effect the car accross the board... not just idle.
is the guy too cheap to get it programmed? have you ran any type of scan on it. might be something as simple as the throttle body blades need to be openned a little

 

I plan to make a little circuit that only bends the MAP
at low TPS. Seems simple enough on its face, a
switched shunt or two on a resistor ladder. But the
details, kind of important.....

He has a GM scan tool for it. He doesn't want to go
and pull the socket to put a ZIF for changing chips.
Cheap, yeah boy. Camping out in his "underground"
shop, is the lifestyle.

 

is his a 92-93?

all i have are the tables for a maf lt1 car... i dont think they will be the same as the speed density.