I have noticed that while driving my Mustang that sometimes it seems to lag. It gets up to 2 grand and starts to go then at around 3 grand it seems to die off some and at 4 grand it really opens up.

Any ideas?

Swirl

 

mabye a dirty fuel filter. don't know

 

I guess I could take some parts off and see what's going on.

It could also be the fact that the previous owner left on the stock cats(?)

Swirl