like when you drive it harder than normal, it'll start to shake all the way to redline? or just for a split second? if its until redline, try testing your spark plug wires, one or more may have a crack in it where it goes over the spark plug, if it does, replace wires....

steps that worked for me:

1: turn off car
2. have friend pull 1 spark plug wire out and lay it on the valve cover (metal)
3: let it sit on the cover and turn on the car, ask if he saw a spark come from where its not suppose to
4: repeat step 2 and 3 for each spark plug wire, but remember only leave 1 out at a time. and do NOT hold the wire. let it lay on the valve cover.

i'd try that, it should take more than 5-10 mins with another friend.. or you can go out and buy new wires hoping it'll work and you made a good choice on the buy... good luck!