My backordered power valve from jegs finally came in 6 weeks later. I went with the 9.5, and my off idle stumble is gone. Now it feels like I actually have alittle low end torque. Should I go down a jet size or two now that the pv is bigger? I read on one of sofaking's posts about most people have to small of a pv and over compensating with larger jets. Any insight would be greatly appreciated.

 

Try it and see. It's the only way to find out. It's a typical "tuning" thing: not a one-size-fits-all, not a look-it-up-in-the-book, none of that. You just gotta try stuff and find what YOUR engine (and car and driver) wants.

As I've posted before, the best way to tune a street-driven Holley is generally to jet it down until it just begins to lean-surge at cruise, which you can often catch the easiest by driving on a stretch of highway with a long, significant slope that's not really "steep"; then go back up 2 sizes. Then install a PV that's about 1-2 numbers lower than the lowest vacuum the engine ever produces when NOT under "power" conditions; most often this will be either idling in gear, or cruising at the lowest cruise RPM you use (like lugging the engine in a high gear when it really ought ot beshifted into a lower one).