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I used to sell tires many years ago, so I have a little something to add to this discussion.

A VW Bug from the sixties was supposed to run 18 psi in the front. It is all based on load. Remember, these cars are LIGHT! You can get charts that list suggested psi for a specific load on your tire.If you run higher pressures, your tire will not have the tread lying flat on the road. We all want the most tread on the road, don't we? Treadwear we don't worry too much, as not enough miles are put on these cars as our daily drivers.

32 psi is WAY too high for these cars(for street driving). Most Speedsters weigh about 1700 pounds or so. Add 200 pounds or more for driver/fuel etc. and you are still under 2000.So about 1000 pounds per side, so even at a 50/50 weight distribution, you are talking 500 pounds a corner. Most of you run a 185/65r15 tire, or close to that. The load range on that tire is in the 80s, it is 86 on page 15 of this: http://toyotires.com/tire-care-safety/load-inflation-tables

Bridgestone lists both sizes I need as load range 88H, 185-65 and 195-60 15. This is 1058 pounds at 26 psi, clearly too high for the small amount of load I am running.

At 26 psi, which is as low as the chart goes, load range 86 will support 1014 pounds PER TIRE which is twice what is theoretically needed. If I remember, you want a little more load capacity than you need, but not twice as much.

My Spyder weighs 1650 with me and fuel, set up for regular driving. It works out to about 350 pounds on each front tire, verified with race scales. I run 18 in the front, 23 rear. Less than 18 isn't enough to keep the sidewalls stiff enough for cornering. But much more than 18 makes the car ride rough, as there really isn't enough weight on the front to allow more pressure.

Get a cheap IR thermometer, take your car for a LONG, spirited drive, then stop in the middle, turn your wheels to the side, and take three readings along the tread, L, center, and R. If the temps are similar, you got it right. That is, assuming shocks and alignment is set right, but that's another story.

Don't overinflate your tires, it may be hazardous to your health, especially high pressure in the rear which can cause snap oversteer, then you slide off the road sideways or backwards.

This seemed like a cool experiment and I have plenty of open track to try so I went out and gave it a go.

I read everything here, then read the VS owners manual, then relied on actual drive time experience.

FWIW The VS manual reads: 22 front / 22 rear.

General consensuses here was higher pressure in the rear verses front.

I first attempted a nice long right hand sweeper onto a left 45 degree at my stated settings of 32/32. The car was pleasant, but still had a touch of oversteer. So... I tried the 22/22 called out in the manual in the same stretch. This was just too soft for my liking. It took away any crispness that the car had (VS stock, no front bar, no camber compensator on 165/15 regular street tires) and felt uncontrolled but equal.

Next I dialed in 18 front 23 rear. It pushed (understeered) like a dump truck, albeit a controllable dump truck.

So I went by feel and dialed 28 front & 31 rear... That actually felt pretty good for my taste.

Now - I have a tire temp gauge - but its 45 degrees here and I doubt I can get reliable readings on my test loop today, so I will save that for another day. But I am basically happy (on my set up) with this number. Your results may vary.

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