% Tire Slip Or Spin

Discussion in 'PSI Superchargers Tech Questions' started by TOL, Nov 1, 2008.

  1. TOL

    TOL Active Member

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    A question for people running beadlocks and 36/34.5 tires.......

    Is there a rough rule of thumb for the % slip or spin that you aim for when "getting up on the tire"? Likewise is there a rough rule of thumb for the % slip or spin which results in best overall acceleration through first gear or beyond?

    I realize that a lot of this is dependant upon a lot of variables. I'm just looking for a starting ballpark idea.

    Thanks.
     
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  2. BLOWN INCOME

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    I Hope Someone Has A Answer For You..i Have Fought Mine For Over A Season Now,and Will Probably Switch Back To Liners Which We Ran Since The 70's..more Air,more Spin,less Air More Bite...can't Get Enough Tire Spin 34.5 M/t, Beadlocs,5.5 Pressure,leaving The Line @4000 With Lencodrive..changed Tire Pressure 2.0 Either Way And Seen No Difference,can't Get It Up On The Tires Quick Enough...yes,i Do Have Plenty Of Horsepower(over 2200)
     
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  3. AnimalCrew

    AnimalCrew New Member

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    Do you have a log of drive shaft RPM? What RPM are you leaving at? What is your present 60'. What's your Engine specs, blower?

    Blown Income - Have you tried leaving around 5000 or 5500? What's your blower overdrive. How much boost at launch?
     
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  4. cd3d

    cd3d New Member

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    hey, guys and specially santo s.
    on the converter door cars i work with there is a range (happy place) of driveshaft rpm. AT .5 out be above 2000 and below 3300 and the car goes smoothly on it's way. too low OR too high and it can shake teeth loose. *** every car is diff.
    santo, most 34.5 slicks work between 5.8 lbs and 6.5lbs
    chuck d.
     
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  5. BLOWN INCOME

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    I Don't Believe In Building A Good Motor And Having To Take 10 Or More Degree Of Timing Out At The Hit(like Recommended By Others Using A Lencodrive,i Run No 6 Shooter).had 4 Different Convertors,30 Degrees Of Timing...if I Leave At Anything Over 4400 I Will Blow The Tires Off,pending On Tracks....blower K-11 Littlefield 14:71 , 45 Over,48lbs.of Boost,96 Aj Fuel Heads...did Go To A Smaller C.i.hemi(450ci) Instead Of A 526ci @2460hp (which I Could Only Leave At 3400rpm) And It Works Better,next Move Is Non Beadloc,hopefully To Get Up On The Tires Quicker And A 470ci Or 480ci....chuck ,you Still Have The Same Phone # ??? Also Tires Are M/t 34.5..
     
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  6. cd3d

    cd3d New Member

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    santo, the base torque of the engine (mostly stroke) the gearing @ hit, weight of car all effect the results. HINT, i have not seen a bad run if .5 pinion speed is 2600. using launch retard have seen good results between -4* and -17* (on different combos. GOOD record keeping and testing are necessary!!!!
    on my own junker, long stroke (4.5) base timing of 33-35*, 2600 lbs. powerglide, hit gearing of 7.72 or 7.38, 34.5 slick (mt,gy,ho all same)
    good track drop to22* ( -13) hold for .5, go to full tilt bye 1.3 sec.
    poor track drop to 17* (-16 from 33*) hold to .7 and full bye 2.o seconds
    best sixty of .990, best 330' of 2.74 best run 4.16 @ 175 mph..
    some shorter stroke cars drop less timing (5-12* ) and get back to full timing sooner. one wild man did a great track run of -4* and back to full bye .9 result 4.02 @ 184. track got better and he shook next rnd> GOOD records and testing required!!!!!!!!!!!!!!!
    hope this helps as is more secrets than i give up in a year!! chuck
     
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  7. AnimalCrew

    AnimalCrew New Member

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    It's pretty much pull timing or clutch unless you run a converter... then timing is probably your best answer. You have to optimize the launch somehow. Putting the coals to it and crossing your fingers doesn't work very often... :D
     
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  8. Dale Finch

    Dale Finch Member

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    Hey guys, there is not enough information here. The tire is hooked to something. What kind of car, engine etc. Is this a PSI funny car or dragster. Suspension car? Wheel speed makes the world go around. Weak shake or too much is two different situations.
     
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