ive been having a weird problem with my cobra. in 1st gear i can take it all the way to red line, 2nd gear will hit a wall anywhere between 5500 and 6000, same with 3rd and 4th. it doesnt hit at the same spot everytime. mods are a 2.8 upper stock blower, arh long tubes w/ off road x pipe, mac cat back, msd 2step, the previous owner installed everything and also said he changed the plugs but didnt say what he put in. has anyone else had this problem?