- #1
mad modder
- 3
- 0
Hi all,
i found this forum while spending ages searching the net looking at limiting voltages, and it seems a good place to ask for advice.
here is the problem i have,
my car when it was normally aspirated it has a sensor that sensed engine load using a map sensor using 0-14.5psi, and then compared the throttle position sensor to work out timing and fuelling.
basic 3 stages of the map sensor are roughly as follows but it is linear:
0-5spi is engine braking 0-1.6v (shuts off or reduces fuelling due to engine braking/slowing down)
5-10psi is normal engine load 1.6-3.32v (2.25-2.5v is tick over voltage when not driving)
10-14.5 is heavy engine load 3.32-5v (full throttle / up hill or heavy weight in car)
now I've turbocharged my car the standard sensor gets the wrong reading for when I'm driving in the normal range. say 0 boost (14.5psi) at 70mph so the engine is thinking it has a heavy load and increases fuelling and timing.
i bought a 2bar map that spreads the 5v over 29psi but the voltage the engine looks for at tickover is too low (about 1v) and the ecu thinks I'm engine braking and shuts fuel off
so i did a line chart to compare different map sensors that use 5v and 12v
i have a 3bar boost gauge on my car that tells me 0-43.5 psi working with an output from 0v-12v respective of pressure, i only use 10psi of boost (22psi) so the max voltage output is around 6v
i need to take the 0-12v feed from this sensor and limit its output when it gets to 5v
any one got any idea's
Regs
Richard
i found this forum while spending ages searching the net looking at limiting voltages, and it seems a good place to ask for advice.
here is the problem i have,
my car when it was normally aspirated it has a sensor that sensed engine load using a map sensor using 0-14.5psi, and then compared the throttle position sensor to work out timing and fuelling.
basic 3 stages of the map sensor are roughly as follows but it is linear:
0-5spi is engine braking 0-1.6v (shuts off or reduces fuelling due to engine braking/slowing down)
5-10psi is normal engine load 1.6-3.32v (2.25-2.5v is tick over voltage when not driving)
10-14.5 is heavy engine load 3.32-5v (full throttle / up hill or heavy weight in car)
now I've turbocharged my car the standard sensor gets the wrong reading for when I'm driving in the normal range. say 0 boost (14.5psi) at 70mph so the engine is thinking it has a heavy load and increases fuelling and timing.
i bought a 2bar map that spreads the 5v over 29psi but the voltage the engine looks for at tickover is too low (about 1v) and the ecu thinks I'm engine braking and shuts fuel off
so i did a line chart to compare different map sensors that use 5v and 12v
i have a 3bar boost gauge on my car that tells me 0-43.5 psi working with an output from 0v-12v respective of pressure, i only use 10psi of boost (22psi) so the max voltage output is around 6v
i need to take the 0-12v feed from this sensor and limit its output when it gets to 5v
any one got any idea's
Regs
Richard