Revamping the entire suspension is what made me feel safe in my car.
For me ,that was front suspension rebuild, all the old rotted rubber pieces replaced.
New leaf springs in the back.
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If you have a pre-67, I'd say getting rid of the spear thru the chest steering column.
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But I feel fairly secure in the car now, with suspension rebuild, 3 point belts, and disc brakes.
Not as safe I as feel in my Passat, but secure.
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While not safety specific, I could also feel a difference in the car with an export brace and monte carlo bar.
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