so, yeah, the reason i created this thread was to show something cool that i figured out. lately the fact that my car isnt making as much power as it could at this boost has been bugging me. so, i wanted to look into what i could do to make more power (aside from turning up the boost, or advancing the timing) the vpc has also been inconsistent with its settings. like it runs rich one moment, lean the next, and in between shifts it felt like i was waiting for the manifold to re inflate, there basically was a lag there. so, i decided to try the lexus afm. the drivability was shitty, but it made good power under boost. not to mention the settings weren't changing. the vpc makes shitty power, but good driveability, plus, when the bov opens my car doesnt loose metered air. i kinda wanted the best of both worlds. this is how i did it...
i bought an adjustable pressure sensor off of ebay for like 18 bucks. using a compressor i dialed it to activate at around 1 or 2psi. then i use the constant pin on the pressure sensor for the afm signal going to the ecu. the other two pins are a normally closed and a normally open. the normally closed goes to the vpc ouput wire. the normally open goes to the afm signal from the afm itself. if the engine boosts, it starts metering the air with the afm. as soon as i take my foot off the gas, and boost goes away it goes back to the vpc. this is nice because i have the nice predictable nature of the afm, and the flexibility of the vpc. what i noticed from doing it, is more power under boost, and i dont have that laggy feeling in between shifts. the power is constant, and smooth. a major improvement over the vpc alone.
i bought an adjustable pressure sensor off of ebay for like 18 bucks. using a compressor i dialed it to activate at around 1 or 2psi. then i use the constant pin on the pressure sensor for the afm signal going to the ecu. the other two pins are a normally closed and a normally open. the normally closed goes to the vpc ouput wire. the normally open goes to the afm signal from the afm itself. if the engine boosts, it starts metering the air with the afm. as soon as i take my foot off the gas, and boost goes away it goes back to the vpc. this is nice because i have the nice predictable nature of the afm, and the flexibility of the vpc. what i noticed from doing it, is more power under boost, and i dont have that laggy feeling in between shifts. the power is constant, and smooth. a major improvement over the vpc alone.
