I run 50 over on my 438k stock motor. I'm using the 8 hole motorsport nozzles. They are stock but flow 50 percent more than the oem. I have used 30 overs on it before. I like the 50s that I have now better. Mostly because of some benefits of the nozzle design.
I asked exergy about getting some 60 over with the 8 hole Bosch Motorsports and was told I couldn't get that unless I went to 350% or up...you have a hookup