i'm assuming your tube car is a four link setup.
most of these cars like a long solid bar. at the very least 64 inches but most are between 72 and 84 unless you have a power adder, then it starts at 84 and goes up from there. i see a few of the outlaw 10.5 cars run a spring loaded bar, but on a big tire car it's usually not needed.
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'78 Ford Fairmont 526ci pontiac; true 10.5 tires and stock suspension.
5.14 @140.5 w/nos; 8.86@151 all motor.8.17@172 1/4 mile w/nos
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