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curt
06-24-2005, 08:12 PM
MY 1955 Studebaker President has 205/75/R15 tires. Max pressure is listed as 35 psi. What tire pressures are are you folks using, around town , on the road, etc?

JDP
06-24-2005, 10:51 PM
28-30 is fine.

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63 R2 4 speed GT Hawk
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rockne10
06-25-2005, 06:58 PM
I usually run what the tire manufacturer recommends on the sidewall; extends tire life and improves mileage. Running less will give a softer ride and should pose no problem.
The problem arises when tires are so underinflated they flex too much, causing friction in the rubber molecules(especially thin sidewall radials), leading to blowouts.

Sircocky
06-25-2005, 09:11 PM
Curt You said the max pressure is 35 lb it probably also said that with max load .If you put 35 lb in the tires and drive on hot roads or park on hot payment you will have more then 35 lbs of pressure.I have seen several rv's with spare on the back of rv under tire cover blow in the heat because a customer would put max air in it . You better listen to JDP . and be safe and have a better ride. Max is not always the best in everything .;)

curt
06-25-2005, 10:04 PM
I lowered the tire pressure ( had driven 2 miles at 35 mph with outside temperature 80)to 30 psi. The ride improved! I think some of my rough ride was related to high tire pressure. I find a lot of little things are out of adjustment on this car. Dwell was 14 when I checked it, now it is 30. The valves were all a bit tight.The car seems to be a good one, it just needs TLC.

N8N
06-26-2005, 04:34 AM
When running non-stock tires (and let's face it, 99% of us are on our Studes) I generally do a little mental figuring relating the actual weight of a corner of the car to the max rated weight of the tires; then multiply that proportion by the max pressure to get a new baseline pressure. I generally add 3-4 PSI to that number as a safety factor.

You can use the "chalk across the tread" method to see if there's any more fine tuning required to get a nice flat tread pattern, and/or use a pyrometer to measure the temperature at various places across the tread after a drive. This assumes, of course, that your car is in aligment...

nate

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64Avanti
06-26-2005, 12:52 PM
Nate is right on in his comments. Proper tire pressure is also related to how you drive the car. If you like to push it in the corners or just want a more responsive car then you will want a little more pressure in the tires. Also the front tires should have more pressure than the rears to improve the handling balance on our Studebakers. This applies to most cars on the road by the way.

David L

curt
06-26-2005, 08:40 PM
I'm a gentle driver. I enjoy driving the Studebaker but I have a desire to avoid jack rabbit starts and stops. So, I will lower the front to 29psi and rear to 27 psi and give it a try. Two tires could support the total car at max tire pressure.

Dick Steinkamp
06-26-2005, 10:33 PM
quote:Originally posted by curt

Dwell was 14 when I checked it, now it is 30.


Check that timing now. 1 degree of dwell is about equal to 1 degree of initial advance. If the timing was right at 14 degrees of dwell it is now probably off by a lot.

-Dick-

curt
06-27-2005, 09:09 PM
Dick, thank you for the timing/dwell statement. It did not register on the timing change when the dwell changes. It was 6 or 8 degrees off, advanced.