I have a maxspeed turbo muffler, plan to geta header and "cat-delete" will I run into "lack of" back pressure? also, Is a Short-Shifter hard to install? thx for any feedback!!!

I have a maxspeed turbo muffler, plan to geta header and "cat-delete" will I run into "lack of" back pressure? also, Is a Short-Shifter hard to install? thx for any feedback!!!

What size is the piping? 2.25? You will notice a decrease in torque but your top end will increase a fair amount.

I installed a short shifter in under 30 mintues, I cant imagine it would be very different for a celica.