When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Some time back I had reported on my work all things steering. Gary did a beautiful job on the steering box while I replaced or rebuilt everything else between the horn button and the spindle. I did remove the damper and I did set the tie rods on the quick steer setting. I have a L79 and no power steer assist. For me the results were impressive and I have commented on how she steers more precise than some R&P's I have owned including my F150. At the time I had Goodyear Assurance tires running 30 psi. This did come with a higher steering effort especially at very low speeds but my shoulders are in good shape and I kinda like the effect especially on the track. I pulled the trailing arms weeks ago and had them rebuilt at Bairs who did an excellent job. Yesterday I finally got the alignment pretty close to what I wanted and mounted Vredestein Classics that have a inflation spec of 51 psi. I set them to 45 psi to start and it would not come as a surprise to you that the steering effort is now reduced by easily 25% over the Goodyear's. An unanticipated additional bonus. I am shooting for a track and tune event in 2 weeks and will see how she does.
Mark, the 51psi is what is embossed on the tire so it may well be the max. I too was a bit surprised but I did a quick google search and 51 is what came up. It's a W-rated tire with the extra nylon wrap so I am thinking 45psi is Ok. Others may chime in on that.
51 psi is the max and 45 seems very high psi to me also for a reasonably light car. In hot weather on the road you could easily pick up 2 or 3 psi and be up close to that max. As long as the tires are sized for a load range within the car manufacturers specifications, pressures for normal driving should be per the car manufacturers recommendations. Of course on a C2 those were for old bias-ply tires so it doesn’t help much. I would think something around 30-32 would be fine but the steering effort is going to increase.
Paul, you could always chalk the tires to know for sure. I used this method on my Jeep when I upgraded to 37x13.50R20 tires.
Rub chalk heavily across the tread width and about 6” of the circumference. I did all four tires to be sure but one front and the opposite rear is probably fine. Drive the car on a relatively flat surface. You should be able to observe an intact chalk “footprint” left behind.
Clear in the middle and thin or missing on the edges says too much tire pressure.
Clear on the edges and thin or missing in the middle says to little tire pressure.
Clear on one edge and thin on the other says camber is incorrect (thin on the inside is too much positive, thin on the outside is too much negative, but evaluate after tire pressure is correct)
Well it was on my list today to check the tire pressures, the young guy who mounted them also inflated them. Good thing, he had 45 psi in (3) and 60 psi in (1). Fortunately I only drove her 10 miles home. I reset all 4 tires to 32 psi and will absolutely use Marks caulk technique to dial them in. Thanks for the tips!
50 psi is the manufacturers' allowable pressure (total). If you pump those tires to 50 psi, you will feel every piece of gravel and spent pieces of gum that have been left on the road in your backside. It will feel like you are driving on four boulders.