you really want straight runners, the dgav ones start curving straight from the head and the internal diameter isnt that big, youd be better off finding a 2nd hand deco one and using that. or make you own manifold- it doesnt have to be stainless steel, mild will do and just paint it.
"Understeer" is when you hit the fence with the front of the car.
"Oversteer" is when you hit the fence with the rear of the car.
"Horsepower" is how fast you hit the fence.
"Torque" is how far you take the fence with you.