Bending tubes
Modification Design Basis
I spent a bunch of time discussing how we wanted to approach the cage mods with Al, we landed on generally following the current TA2 design of two A Pillars with an Eyebrow and roof X-Brace. This gives a really strong driver containment area with good driver access/egress and visibility within the confines of a current generation body.
A Pillar and Eyebrow Bars
First to be bent and installed are the A Pillar bars and the “eyebrow” bar. The A Pillar bars have 3 bends and a 10 degree offset. The forward most bend is 63 degrees, the mid bend is 25 degrees and the rearmost is 35 degrees. The 10 degree offset is between the 63 and 25 degree bends with one bar offset left and the other to the right. The Eyebrow bar has a 35 degree bend each end. Time was taken to fishmouth each bar for a close fit for welding.
Test Fit of Body
With the A Pillars and Eyebrow bars in place the body was reinstalled to confirm fit. We also installed the seat and did a driver test fit to make sure visibility was not impeded by the bars
X Brace
Next to fit was the X Brace in the roof area. The X is formed with a continuous bar from driver’s side at the main hoop to the intersection of the Eyebrow and A Pillar on the passenger’s side, along with two bars run the opposite direction meeting the continuous bar in the middle of the roof. The pic here is before adding the last bar. The X has a 10 degree bend to optimize the fit with the roof
Braces and Driver Access
Driver access in these cars can be tight at best so I opted to follow along the lines of the current TA2 chassis design which gives much better driver access/egress clearance than the original ASA/GTA design. The drivers side upper horizontal NASCAR bar was removed and a vertical brace added to extend the forwardmost vertical NASCAR bar to support the A Pillar. A diagonal brace was added to tie the main hoop into the rearmost vertical NASCAR bar.
On the passenger side the forwardmost NASCAR bar was extended vertically to support the A Pillar and the upper horizontal NASCAR bar extended to meet the A Pillar also.
Net result is similar access as in my current AI Mustang using the Howe TA2 basic design elements. It’s all tacked in place for now, next step is to weld it all out then its out for blast and paint.