Random hissing noise

[SVOeric]

sounds like a question for another thread, but do some searches learn the difference between BOV and BYPASS valve

BOV's are not the best fit for an SVO (altho dual piston will work somewhat decent)

[CodySvo]

Okay thanks, I've been looking and I think I may have figured it out. I still have a small problem thought it's not big, but when I smash on the gas at low rpms when the boost build it seems like it has a ignition miss still. Like it kinda hesitates a little and pops then as soon as the rpms get above like 3000 it takes off like a rocket.

[svono50]

Sounds like you may be running a little lean below 3000. 3000 is when the EEC goes into open-loop control mode and basically ignores the O2 sensor, so it starts just dumping fuel based on its internal tables. When you look at a dyno plot of a stock SVO you can see this transition pretty clearly as the A/F ratio goes way fat and eases up as you go up the rpm scale.

Try gapping your plugs a little bit tighter (.028-.030) and see if that helps any.