okay so i thought my cat on my blazer was plugged so i cut it off and put 2 1/4 inch straight pipe on but im still having an issue if i get on the truck and make it spin tires on take off once i get at 50-55 itll shake til i let off the gas and it doesnt always do it only when i play a little and it smells like its running really rich.

 

I wonder what you're driving, but if it only does this under the condition you specified, then the solution is simple...quit doing burnouts when you take off.
Oh...and put a catalytic converter back on. Taking it off does nothing to help the performance.

 

its a 92 4 door 4x4 4.3l vortec i dont do burnouts dai;y only did it to because it was raining and i was on a hill i ***** foot this truck cuz it is my daily vechicle not a toy and cutting the cat off has not made it better nor has it made it worse but i did recently change plugs wires and d cap n button. oil n filter and tranny filter now it doesnt do it so i think it was one of those was the issue

 

oh and i put a missing bolt from the tranmission to the cross member in so i actually think that was the reall cause because the bolt that was not missing was about to snap changed them both