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sbdeadelf · 12-05-2009, 05:31 PM

Not a lot of change in diameter:
For the 155R12 the diameter was SUPPOSED to be 21.8, but actually measured 21.3 if memory serves.
For the 155/60/15 the diameter was around 22.3 inches. From actual driving, the speedometer which USED to be absolutely dead-on, is now about 6% under the actual mileage. With the 12's, max pressure was around 35psi and with the 15's max psi is 44. Also, I trust Continental more than most of the 155R12 makers, but they do cost more.
Handling is exeptional, especially compared to the 12s. Another nice thing about the skinnies, is that even at 1650 lbs, you just do NOT hydroplane.
As for testing, there are just too many variables to get good results in a tank-fill test. I just can't use up fuel fast enough to get a result that's meaningful. By the time I'm ready to fill up more than a gallon, the temp has changed, the winds have changed, etc.
I keep drooling over the 135/70/15's they have access to in EU!..... unless someone proves the 'wider is better' thing correct. Then I'd have to re-think a lot of things! Oh NO!

12-05-2009, 05:31 PM	#14 (permalink)
sbdeadelf EcoModding Lurker Join Date: May 2008 Location: Santa Barbara, CA Posts: 10 Thanks: 5 Thanked 0 Times in 0 Posts	Not a lot of change in diameter: For the 155R12 the diameter was SUPPOSED to be 21.8, but actually measured 21.3 if memory serves. For the 155/60/15 the diameter was around 22.3 inches. From actual driving, the speedometer which USED to be absolutely dead-on, is now about 6% under the actual mileage. With the 12's, max pressure was around 35psi and with the 15's max psi is 44. Also, I trust Continental more than most of the 155R12 makers, but they do cost more. Handling is exeptional, especially compared to the 12s. Another nice thing about the skinnies, is that even at 1650 lbs, you just do NOT hydroplane. As for testing, there are just too many variables to get good results in a tank-fill test. I just can't use up fuel fast enough to get a result that's meaningful. By the time I'm ready to fill up more than a gallon, the temp has changed, the winds have changed, etc. I keep drooling over the 135/70/15's they have access to in EU!..... unless someone proves the 'wider is better' thing correct. Then I'd have to re-think a lot of things! Oh NO! Last edited by sbdeadelf; 12-05-2009 at 05:36 PM..