VE Table Blending for ITB: "Multiply MAP" and "SD --> a/n"?
Posted: Mon Jun 09, 2025 2:46 pm
Hello everyone,
I have a few newbie questions and hope for your support: So far, I've converted several engines to Megasquirt and Speeduino. I'm toying with the idea of switching my own Caterham's platform from Speeduino to Rusefi. Why? It's an NA engine with very high specific power (240hp from a 1.8 l), ITBs (specifically, roller barrels) and quite extreme camshafts.
I'm speculating on improvements in the low-load range through table blending, but unfortunately I don't fully understand the system and can't find any documentation or examples.
Question 1:
I'm currently using "Alpha/n multiply MAP." This means that the VE is simply multiplied by the MAP value to achieve better and "smoother" load sensing at lower TPS: e.g., 70 kPa means VE x 0.7 --> the VEs therefore get larger. At full load (~100 kPa), VE x 1 = no effect.
How can this be replicated in Rusefi? Is option 1 or 2 correct (see screenshots)?
Question 2:
Is it possible to completely "blend" from speed density to alpha/n? What would the corresponding tables look like?
Bye
Dominik
I have a few newbie questions and hope for your support: So far, I've converted several engines to Megasquirt and Speeduino. I'm toying with the idea of switching my own Caterham's platform from Speeduino to Rusefi. Why? It's an NA engine with very high specific power (240hp from a 1.8 l), ITBs (specifically, roller barrels) and quite extreme camshafts.
I'm speculating on improvements in the low-load range through table blending, but unfortunately I don't fully understand the system and can't find any documentation or examples.
Question 1:
I'm currently using "Alpha/n multiply MAP." This means that the VE is simply multiplied by the MAP value to achieve better and "smoother" load sensing at lower TPS: e.g., 70 kPa means VE x 0.7 --> the VEs therefore get larger. At full load (~100 kPa), VE x 1 = no effect.
How can this be replicated in Rusefi? Is option 1 or 2 correct (see screenshots)?
Question 2:
Is it possible to completely "blend" from speed density to alpha/n? What would the corresponding tables look like?
Bye
Dominik