My friend has welded in braces out of I-beams under the car- made out of some speciall alloy that is just as strong as iron but with the lightness of a aluminum. We can jack the car up in the front and U can open anything on the car and it will not bend the unibody- hes got hydros on his 4 door B13 so the chassis gots to be extra stiff or U will not open the doors afterwards. Mike Jez