NEED HELP FOR TUNING ! APEX MPI S/C STAGE 2

Boosted!!

What mods are done to your engine? I run 15 pounds of boost with no BOV. 20 pounds of boost consistantly pounded through an apex will destroy your engine unless you have the necessary upgrade mods to the internals. There really isn't as far as i know a stand alone fuel system for the apex yet, only the piggyback type that I'm aware of and they can be a bit frustrating. If you have to give it gas to make it idle then your low end idle mixture needs turned up. I run the MPI GEMS controller and I too was running 20 pounds of boost. Way too much!! The best way to turn down the boost on an apex is change the gears that run from the crank up to the shaft. Believe it or not there are several different combos and they all work!! Slowing down the supercharger decreases the boost plus ads longevity to its lifespan. Back to your problem. 20 pounds of boost requires a whole bunch of fuel and more tweaking with your controller. Every sled is different. I can run at 3/4 throttle at 15 pounds consistantly but when doing a full pull at WOT it decreases to 10 pounds firm. Make perfect sense because At WOT all throttle bodies are open all the way consuming more of the pressure than that of 3/4 throttle. Thats just nature of the beast because it is a controlled environment and isn't exponential like its big brother the TURBO.. If your sled makes a popping sound other than your rev limiter then chances are its lean and needs much more fuel under boost but I haven't ran with any other controller other than the GEMS. so I don't know how to adjust yours. Mine was difficult to get dialed in at 20 pounds but after i changed out the drive gears under the oil tank it became much easier to dial in. Without a stand alone fuel management system, you are going to have to do it the old fashion way, Trial and error. Play with it and remember what settings do just what to your performance and you'll know. The lack of fuel delivery is most likely the cause of its poor performance not knowing what mods have been done. Just bare in mind that what works for one sled might also be the death of another.