With my ebr ecm I left the dobeck at its recommended settings or if box, but I can fatten up the fuel on the fly if I need to, I will be honest I actually used the tfi without the ecm in beginning and took it off once I got the ebr ecm but something was missing and when I put it back on it put tears in my eyes and a smile on my face! Basically if you are not a tuner and don't do computers this will let you tune like a carburetor most people here like the computer version though!