Lift and Spring Bind...How Close is Too Close
09-29-2006, 04:16 PM
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Car: 1988 IROC-Z
Engine: 350 TPI
Transmission: WC T5
Lift and Spring Bind...How Close is Too Close
Quick question
Valve springs in question are said to be good to .550". Planned cam and rocker swap put me at .544". Is this too close for comfort?
Steve
Valve springs in question are said to be good to .550". Planned cam and rocker swap put me at .544". Is this too close for comfort?
Steve
09-29-2006, 05:22 PM
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Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
"Good to" should be "good to". Coil bind is a different issue.
You should have .050"-.060" minimum valve travel (valve fully closed to retainer hits guide/stem seal), and installed height minus coil bind, more than lift at valve.
You should have .050"-.060" minimum valve travel (valve fully closed to retainer hits guide/stem seal), and installed height minus coil bind, more than lift at valve.
09-29-2006, 07:33 PM
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Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
At max lift, you should have a minimum of 0.060" between the coils. You also need to check to make sure the underside of the spring retainer isn't hitting the top of the valve guide/seal. Regular stamped steel rockers don't have the center slot long enough for much lift over .500". Long slot rockers or roller rockers need to be used.
What the springs are good to means nothing is they're not set up properly.
What the springs are good to means nothing is they're not set up properly.
09-29-2006, 07:45 PM
#5
Here is a good thread on the subject by some well known engine builders. Valve Spring Tech: Must be used close to coil bind ? :: Speed Talk - Auto Racing Forum.
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