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slick air pressure

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Old 06-13-2003 | 08:12 PM
  #1  
mean 5.7's Avatar
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From: plainfield il
Car: 87 gta
Engine: 5.7 ltr
Transmission: full race 700r4
slick air pressure

what psi should i be running my goodyear 26-10.0-15 slicks

they do have tubes.
Old 06-13-2003 | 08:52 PM
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AlkyIROC's Avatar
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
What does goodyear recommend?

The goodyear web site offers nothing. Hoosier and MT both suggest no lower than 18 psi on a heavy car, 3200+.

Start at 18 and go up 1/2 pound at a time until you get the best 60' time. They're no magic number since each car is different.

I run anywhere from 12-16 in my slicks.
Old 06-13-2003 | 10:21 PM
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mean 5.7's Avatar
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From: plainfield il
Car: 87 gta
Engine: 5.7 ltr
Transmission: full race 700r4
thank you. your just the person i hoped would reply.
my car with me and a full tank of gas weigh 3175lbs.

i will be running the slicks for the first time in iowa on the 21st
any pointers or things i should know about launching on slicks
Old 06-14-2003 | 12:47 AM
  #4  
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Since your car is light enough start at 20 psi and go down 1/2 pound at a time until the best 60' time is achieved.

Launching with slicks is no different than launching with street tires. The main difference is you need to heat them up first.

Different brands have different procedures. Roll into the water box to get the slicks wet. A wet tire spins easier than a dry tire and doesn't wear the rubber off as quickly. Since every car is different, here's what I do for a burnout.

I set my line lock so that there's no drag on the rear brakes. Holding regular brakes will work. Only enough pressure to hold the car is required. I start off in first gear and quickly shift to second. I hold it at around 5000 rpm for a few seconds then shift into third. I release the line lock then let the car power it's way out of the water box about 10 feet or so gradually letting off the throttle. Depending on track conditions, I may do a dry hop after that just to see how well the tires are hooking up.

You need to be in high rear when you come out of the water box (automatics). Just in case the tires grab dry pavement and stop suddenly, you won't destroy the tranny. That's the #1 cause of intermediate sprag failures in GM trannies. Once you're in high gear the 2 drums are turning the same speed.

The key to a good burnout is wheel speed. You don't need to do a John Force burnout. Just watch in the mirror until you see tire smoke. That's usually all you need.

MT recommends a good long burnout at the start of the day then only short ones after that.

The burnout in my sig picture was a little longer than required but it made a good picture.
Old 06-14-2003 | 11:45 AM
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mean 5.7's Avatar
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From: plainfield il
Car: 87 gta
Engine: 5.7 ltr
Transmission: full race 700r4
thanks
Old 06-14-2003 | 06:48 PM
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From: north plainfield, nj
Car: 05' GTO
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would that be the same way of doing it with DOT slicks? becuz im gettin a good pair of M&H dot slicks, there just like the MT ET streets but the set im gettin is like 50% used.
Old 06-15-2003 | 01:47 AM
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
ET Street slicks are the same as drag slicks except they have a couple of grooves in them to pass a DOT rating.

All "slicks" work with lower air pressure. The trick is to find the best air pressure that gives the best 60' time. Any radial tire can't run with low air pressure. The sidewalls won't roll over the same way because of the steel belts. When air pressure is low in a radial tire, the center of the tire rolls up off the ground giving less traction.

Tubbed cars running 33" tall 16" wide slicks usually only have 5 psi in them.

A radial tire doesn't like going below 28 psi.
Old 06-15-2003 | 01:57 AM
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Stephen, when you say high gear for automatics you mean 3rd gear right?
Old 06-15-2003 | 08:38 AM
  #9  
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Whatever 1:1 is. Usually third.
Old 06-18-2003 | 07:39 PM
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StreetRCR's Avatar
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From: Illinois
Car: 82 Pace car
Engine: Small block
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Originally posted by Stephen 87 IROC
Tubbed cars running 33" tall 16" wide slicks usually only have 5 psi in them.
NO NO NO NO NO

DON'T go lower than 10 lbs. on any slick. I use 13 lbs. on my car and it's fine. I know no one that goes lower than 10 even the big tire pro stocks and Super Comp Dragsters. If you don't hook then it's time to start looking into other traction devices.
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