Tuesday Tech Question

Question:

I have a ’73 Duster that I compete in Pro ET with at my local NHRA track.  The car currently has a roll bar in it.  The car has a back-half installed, but the firewall, floor, and body are all stock.  This offseason I plan to build a new engine that should put my car into the low 6 second range in the eighth mile.  Will I need to install a complete roll cage?

Duster Dave

Answer:

Duster Dave,

If your car will be running quicker than 6.40 in the eighth mile or 10.00 in the quarter mile you will need a roll cage even though you have an unaltered firewall, floor, and body.  Between 10.00 (6.40) and 10.99 (6.99) cars with your configuration are only required to have a roll bar so long as it is not a convertible.  Cars without an unaltered firewall, floor, or body running 10.99 (6.99) or quicker or faster than 135 mph must have a complete roll cage. 57769