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OPG's, pulleys and shift points for whipple 2.9

Discussion in '5.0L Coyote V8 Engine Modification/Discussion' started by gt347mustang, May 7, 2018.

  1. gt347mustang

    gt347mustang Well-Known Member Established Member

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    Helping a friend dial in a 2017 auto car.

    Only mods are gen 3 Whipple, 132mm tb, long tubes and supporting fuel. Currently running 3.25" pulley but plan to run the smallest possible upper without belt slip on stock 6 rib lower.

    Current shift point is 7000 for fear of shattering factory opg's. Would like to rev it as high as safely possible after installing gears. My question is how high could we turn it once the gears are installed; and what upper pulley can we run without slipping at 7500+rpm on the 6 rib?

    Haven't had it on the dyno yet plan to experiment with different air fuel and timing once it's all assembled. We're currently at 0.82 lambda and 20-23 degrees of timing on e40 fuel and plan to shift both those on the dyno to see what the car actually likes.

    Any input from those with a similar combo would be appreciated. We just want to make sure we're headed in the right direction with mods before pulling the trigger on gears and pulleys.
     
  2. beefcake

    beefcake Authorized Vendor Authorized Vendor

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    Zemedici likes this.
  3. gt347mustang

    gt347mustang Well-Known Member Established Member

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    Thanks Terry. Good advice right there! PM incoming. We're gonna do opg's.

    What's the smallest paxton pulley you typically run on the 6 rib setup? And what rpm do you shift at after installing boundary opg's? I know it's not apples to apples comparison but we're just trying to get an idea of how small we can go on the 6 rib with the Whipple.
     
  4. gt347mustang

    gt347mustang Well-Known Member Established Member

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    Oil pump gears ordered. Will be delivered and installed Saturday.

    Anybody have input on pulley size and or new rpm limits?
     
  5. Sean@LethalPerformance

    [email protected] Authorized Vendor Authorized Vendor

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    On Paxton cars you might start to run into some slip once you got down to a 3.47 pulley. I started to see some up top with my 3.33 gated to 11lbs. 8 rib and and 20% lower completely eliminated that seeing 13.5-14lbs now..

    And yeah good move with the oil pump gears and cranks sprocket, definitely some good insurance if the cars going to be seeing high rpms, especially on boost.
     

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