Time to Fix It Right

The biggest issue is you don't know how the engine was rebuilt, being you don't know the true static compression. To do it right you at least need to pull the heads and see what is going on.

If this we're mine to tackle and i didn't want to remove the heads, I'd put a smaller cam that works with the stock converter and possibly a Performer or Action Plus intake betting it has re-builder or stock replacement pistons sitting in the hole and open chamber stock heads. I hate Avengers so I'd sell it for a Eddie 625 AVS, Street Demon, or 3310 Holley. This all if you want a cruiser that is easy to drive with some fun factor. Sort out the exhaust, Jegs and Summit make a kit. Headers if you want, Dougs and TTI are the best for the street.