demon carb tuning
ok, here we go. I just got a 625 road demon for my 350 monte ss(224 cam, stock 71 heads, edelbrock performer intake, headers, dual 2.5s, other basic stuff). Well the car runs good, but it had a bad stumble between 900-1300 rpm and the mixture screwes did nothing. I called BG and they said my cam was too big for the carb so the erratic vaccuum was creating a lean stumble. So i switched my vacuum advance to manifold instead of ported, which raised my RPM so i lowered the idle speed back down. Stumble is nearing gone, but the car doesnt respond to well to full throttle until it gets over 3000 rpm. If i lay into the carb slowly there is no problem. Also, my primary floats are at almost 3/4 the window and it runs best at that spot, secondaries are at 1/2 window. either way the car doesnt not feel consistant, some days it runs like a bat out of hell with no stumbles, and other days it fights me all day to accelerate smoothly. Im running 7.5 pounds of fuel pressure and BG said that was ok. I noticed too that the floats some times change levels without me touching them. I know this is alot of rambling, but i just want this carb to run at full potential and its inconsistancy makes it hard for me to determine what will help!
PS Im trying to go to atco since they opened but every race night my car runs like ****, and days when the tracks closed it runs great!! WTF!