Has anyone gutted their converter - the one that is between the headers and the y-pipe towards the front I think it is only on Cali spec models. Would that increase accelaration at all?
I tried searching but couldn't find anything about the front one.

 

Theres been a few people who have swapped to a fed spec manifold and used a fed spec y-pipe. Yes it will improve performance.

 

Fed spec conversion will net you power, but gutting the cat and leaving the shell there just creates a bunch of turbulence in the exhaust. May or may not give power, but I personally am not a fan of the whole gutted cat thing (even though Merlyn's and mine both are...).

 

I already have an aftermarket y-pipe so that means I would have to get a fed spec one if I was to get a fed spec manifold?

 

I have done it....its not hard at all. Just find a fed spec header, fed spec y pipe, and an o2 simulator.