A couple things to look at. Check the DOT date code on your tires. If they are older than 6-7 years, they have hardened and will need a lot more heat (hard to achieve on the street) to develop the usual grip levels. The older tires can really impact braking ability with non-abs.
Another thing is driving style. When driving a non-abs car, you have to allow a little time for weight to transfer before applying full brake, or the front will skid prematurely. With abs, we often develop a habit of stabbing the front brake in emergency situations and abs takes care of the rest. Instead, I would try a quick squeeze with rapidly increasing pressure over 0.5-1.0 seconds. That additional compression time can make a big difference on your car's ultimate stopping power. Try it on an empty road and test it out.
Stiffer springs and dampers will also impact weight transfer and weight transfer rate, but I would look at the other 2 items first.
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