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    Results 1 to 6 of 6
    1. #1
      Join Date
      Jan 2020
      Posts
      2

      Cant stop dropping valves

      I have an LQ9 in my 02 silverado. My intitial problem resulted after the planetary gear in the transmission went out. seemed to have over revved and mushed the valve. Perhaps it didn't close in time, or it just went haywire at the higher rpm range.

      I had Richard Godly rebuild it out of Moultrie, Ga as he had built it previously. However, 500 miles, and two days later it all but locked up on me.(dropped valve). I found another OEM head and sent it to Bill and Jeff Ford to have them put it on the flow bench to match the original build.

      After the reassembly it went about 5,000 miles being babied. and I mean babied. for it to drop another valve...

      Where Am I going wrong here? too much lift from the cam?

      I ran this truck hard for 2 years with no problem until the transmission went out causing the first valve to drop. and now it seems like an uphill battle.

      Considering going to Trickflow Specialty heads this time around...but can anyone shed any light on what else might be happening?

      Any help is appreciated.

      sincerely,
      a man tired of pouring out money

    2. #2
      Join Date
      Jan 2020
      Posts
      2
      UPDATE: I have been talking with texas speed. and thinking my lift is 0.606. perhaps even most of the heads you purchase aftermarket are maxed at 0.550. maybe the valve spring seat wasn't milled out with enough clearance? could this explain why it took so long for it to drop another valve??

      Does anyone have a recommendation on a set of heads that can support this kind of lift without going on the bench? Or am I stuck to have even the Trickflow Specialty heads sent off to be milled out for clearance??

    3. #3
      Join Date
      Feb 2016
      Location
      SoCal
      Posts
      475
      .606" lift is honestly not much. The lift definitely isnt your issue. Now if you are running into coil bind, thats an issue. The main reason I have seen valves drop is cause the clearance to the guide is too small.
      1970 VW Bug - Just your average mid engine Bug
      Track toy - 06 Evo - E85 and lots of boost
      Newest track toy - 2021 Supra

    4. #4
      Join Date
      Sep 2006
      Location
      Southern Indiana
      Posts
      4,699
      Country Flag: United States
      I'd have swapped all the valves for new one piece stainless like ferrea or other name brand. Also make sure springs aren't binding and proper length.
      Lee Abel
      AFTERMARKET PERFORMANCE

      1977 Chevy Monza 2+2:Project "Cheap Trick"
      1978 C10 Long bed , On air and trailer puller
      2006 Buell Blast ,Just a bike to ride and for mileage
      1966 Caprice 4dr Sports Roof fact.327/now 350/SOON 454???? Project "II Old,,,ZERO BUDGET OR LESS CAPRICE!"

    5. #5
      Join Date
      Sep 2008
      Location
      Jacksonville, Florida
      Posts
      629
      Country Flag: United States
      I'd say your issue is with the builder...Could be coil bind, valve guide clearance, etc, but all related to the machine and assembly guy.

      You have a great engine shop very close to you, Mike @ WildCat Performance Engines 5179 GA-33 N, Moultrie, GA 31768
      Craig Scholl
      CJD Automotive, LLC
      Jacksonville, Florida
      904-400-1802
      www.cjdautomotive.com

      "I own a Mopar, I already know it won't be in stock, won't ship tomorrow, and won't fit without modification."

    6. #6
      Join Date
      May 2015
      Posts
      249
      Country Flag: United States
      Ask for Dave or Rich, @ http://www.proheads.com/







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