Why is the factory recommended tire pressure in my 1979 Catalina so low? The door jamb recommends 26 PSI, which seems really low, the tires definitely lose some roundness in the contact patch. I have a minor concern that this lower pressure could eventually damage the tires.
I've considered raising the air pressure to closer to 32 PSI, where most modern cars keep their pressure. Will that noticeably impact the handling of the car? These old boats have a lot of body roll, so I can see too stiff of a sidewall from the highwr pressure causing the suspension itself to move further than it should.
The tire pressure was set low by the manufacturer to give the cars a floaty, cushy ride. In the 1970s the World War II generation was still a big market for full-sized cars and that's what most of those customers wanted. The definition of "handling" was considered to be how effortless the steering was and how easy the car was to park. Hustling around corners was not in the picture.
I usually run around 30 psi on older cars, 32 should be fine. If you ever need to replace the steering box consider installing a quick-ratio job made for a Pontiac Trans-Am. With that and heavy-duty springs and shocks plus decent tires you'd be surprised how those old barges can handle.
I can't imagine how horrifically bad the gas mileage was in these cars back in the day, lol. The cushy, floaty feeling is nice on the highway, but taking a corner just a hair too fast is kinda frightening, lol. I accidently did it on my way to work and stuff in the back seat went flying across it from body roll, haha. Where would you find the heavier duty springs and shocks? I need to replace the shocks at least. They're 113k mile originals.
It's been quite a while since I rebuilt the suspension in my old wagon. I think I got the springs from Eaton spring and I specified them to be heavy-duty. (Eaton springs are made in USA!) I forget what shocks I used. See if KYB shocks are available for that car. The Trans-Am steering box is a bolt-in. (Though when I installed mine I did not realize that it had internal stops which are not used in AMC applications. Works fine but you need a football field to make a U-turn! Won't be a problem in a GM car.)
I'll look into that! I may not do the steering box modification for a while, I need to get a few other things fixed, but the coils and shock absorbers are definitely doable.
Maybe 1979 shock absorbers weren't as good as today.
I'm sure there's no harm running 32#
My wife's car specifies 26 psi. I run them at 30 psi. Have for 18 years, no problem.
