Odd question about tires

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DERICKS

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I was looking at still pic's of my car going down the strip and as much as 100-150 feet out the sidwalls are still wrinkled. Is this a problem with inflation? or is it a problem at all? The tires are MT ET Steets 28x13.50x15 and I was running them at 12lbs, the car weighs 3150 with me in it. Am I DRAGGING an under inflated tire down the strip?

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If your car is accelerating hard the tires will have wrinkles all the way down. Have a friend check your black marks on the starting line. Low air pressure will cause two dark lines at the edge of your tire print. To much air will cause a dark spot in the middle. Even darkness all the way across is what you are after. Heavier cars usually need alittle more air, you should be close.
Did you say 13.5 wide tires? What size of a rim are they on? Is the rear tubbed?
 
The tires are listed as 13.5 by MT, they have a 13.2 bulge and 11 inches of tread. The tires are on a 10 inch rim with 5/5 spacing, the wheels tubs are split and widened 3 inches
 
Ideally, you want as much pressure in the tire as you can. You should only lower it for traction. If it'll hook at 22psi, then don't run 12psi. Or whatever.
 
As ray79rt said, the contact patch is your best indicator. Adjust air pressure until you get a nice even, full width, black mark on launch.
 
I run about the same size in Hoosier QTP, they like about 15 lbs....play with the tire pressure and keep an eye on your 60' times.
 
I agree with Dusterdon.

Run as much tire pressure as you can while achieving the best 60' times.

Different car, but my friends have a 10.60 Cuda with 275/60MT's. They run 19-20psi in the tires. It 60's about the same with 14psi too, 1.45 range, but isn't as stable up top.

Contact patch is a good start point, but, isn't the end all be all. You really don't want a "dead hook". If the car is overtired, too much contact patch might not let wheel speed come up. With that situation a little more tire pressure than normal might actually help get the car moving.
 
Ok were on the right track here and let me explain why I'm concerned about the tires in the first place. I had MT Sportsman Pros on it in the same size and at 18lbs of air, they spun ever so slightly when I ran it a few years back. I switched to the ET Streets and they dont spin at all. With that being said the car 60 foots just as good spinning the old tires as it does hooking with the new ones, the 1/8 Mile ET and MPH have dropped with the new tires...about 1 tenth and almost 3 MPH the overal ET and MPH are relatively the same. I guess I'm getting at did I over tire my car? and will pumping them up till they spin a bit defeat the purpose anyways. Should I look at working this out in the carb or should I loosen up the converter?
 
12lbs seems a bit low.. i run m/t drag radials and depending on track conditions they like between 15-18 lbs,car launches hard and most importantly straight..
 
I'm suppossed to be going back on the 1st of November so I will definately go after the air pressure first then look at the carb. I need to clean up the launch and get that tenth I'm looking for
 
I found out where my MPH and ET went! My ET Streets measure 27 1/2 at 18lbs of air and my old Sportsmans measure 26 inches tall at 18lbs of air! The funny thing is both ties are listed at 28 inches tall! I gained 1 1/2 inches of gear killing tire...thats why I was trapping almost 400 rpm less with the tire change.
 
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