can someone please explain to me what is body flex and why/how with a rollcage on a hatchback i can overcome flex?

 

body flex is when the car wants to and does twist like when launching a car at the track. why does it do that because they are unibody cars. you can over come it with a roll cage because of it stiffing up the body in lets just say 6 points on the car. 2 in the hatch 2 behind the driver 2 in front of the driver. that makes the whole car connected allot better so when it twist or tries to it cant because it end up having the rest of the car move with it. like grab a piece of paper one sheet hold it in two hands and twist your hand in opposite directions the paper twist. now if you had lets just say reinforcements going from each corner and the two middle out side sides to the center kinda it would be harder for you to twist that paper. thats the method on a roll cage. i hope you like my drawing of a roll cage for you. now like it would be hard to twist that paper you still could because of it being a piece of paper but it would stop or limit the amount of flex. i love my artistic abilities.

 

great great info!!! and nice diagram

 

I'm sorry and don't mean to be rude... but if the OP had to ask what body flex is and how a roll cage helps to prevent it, then common sense is more common with some people than others.

 

^^
funny

 

put some full length subframe connectors on there... no more flex, cheaper than a cage.

you only really need a cage if your car runs faster than 11.00 in the 1/4

 

or if you run faster then a 13.99 at my track in a 'vert........

 

you will need a roll bar at 11.50 and will need a roll cage at 9.99. like said sub-frames will help with flex but it will still do it and it will still do it some with a bar or cage. what is the big worry here?

 

if the chassis is too stiff, it can crack in spots....

 

Ya that sucks because verts look so ugly with roll cages