There is going to be several factors that determine when the outboards come in. I use yellow springs which a factory springs I also use a fairly gnarly hydraulic cam but I guess to keep it fairly straightforward I would say generally at wide open throttle around 3,000 RPMs. The outboards butterflys need move freely.- the diaphragms will fail I've had to replace mine once. If you don't think you're outboards are coming in then they're definitely not. You would know.