I bought genuine Nissan seals about a year ago and it cost me over R400... the exact same o-rings from a Seal (not the type you go clubbing... lol) Company cost about R40 for all four injectors...
Can't rememebr the name of the company, sorry man... let your fingers do the walking...
Understeer is when you hit the wall with the front of the car and oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall, torque is how far you take the wall with you.