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    Results 1 to 8 of 8
    1. #1
      Join Date
      Jul 2020
      Posts
      24

      DSE steering rack ratio

      Does anyone know the steering ratio of this rack?

      They donít really mention it on their page.



      https://www.detroitspeed.com/21-5-de...t-frame-090220

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      Rick
      65 Fastback Mustang
      89 Daytona Shelby
      18 Charger R/T Superbee


    2. #2
      Join Date
      Nov 2006
      Location
      Mountain Springs, Texas
      Posts
      3,760
      Country Flag: United States
      20:1 as far as I can recall.

      Don
      1969 Camaro - LSA 6L90E AME sub/IRS
      1957 Buick Estate Wagon
      1959 El Camino - Ironworks frame
      1956 Cameo - full C5 suspension/drivetrain

    3. #3
      Join Date
      May 2018
      Location
      San Diego County
      Posts
      65
      Country Flag: United States
      My understanding is that it is a 20:1 as well. We actually have one in the shop, purchased several years ago. It seems to have a significant internal steering stop, the amount of full lock angle is really "low." Will validate that in a comparison with an AGR Cobra rack in the next few days.

      Most of the other SN-95 racks are 15:1 with some being even quicker. I read somewhere that DSE uses shorter steering arms to accommodate the slower ratio so keep that in mind too, have not validated but it would make sense.
      Mark Magers

      Founder and Principal, Lateral Dynamics LLC
      [email protected]
      lateral-dynamics.com

      One tenth of a second on the race track is often the difference between first place, and fourth.

    4. #4
      Join Date
      Dec 2006
      Location
      Moving from Burbs of Detroit to my native homeland, the woods of Cascadia
      Posts
      1,724
      Country Flag: United States
      Don't you need a steering arm to calculate rack ratio? I do see that these are to be paired with an alumiframe front end, that steering arm would provide a ratio.

      I have seen rack travel /revolution before.

      And 20:1 seems awfully slow, particularly if you autocross a car
      Greg Fast
      (yes, the last name is spelled correctly)

      1970 Camaro RS Clone
      1984 el Camino
      1973 MGB vintage E/Prod race car
      (Soon to be an SCCA H/Prod limited prep)

    5. #5
      Join Date
      Nov 2006
      Location
      Mountain Springs, Texas
      Posts
      3,760
      Country Flag: United States
      Quote Originally Posted by Twentyover View Post

      And 20:1 seems awfully slow, particularly if you autocross a car
      David Pozzi has complained about the DSE rack being slow but he has it on an Art Morrison subframe.

      Don
      1969 Camaro - LSA 6L90E AME sub/IRS
      1957 Buick Estate Wagon
      1959 El Camino - Ironworks frame
      1956 Cameo - full C5 suspension/drivetrain

    6. #6
      Join Date
      May 2018
      Location
      San Diego County
      Posts
      65
      Country Flag: United States
      Quick note about the steering stops, well, most likely. For sure the AGR Cobra style rack, on my setup, has at least 3 degrees of additional steering angle, at full lock, inside tire. Reasonable measurement method but not 100% accurate, good enough to see quite a difference though.
      Mark Magers

      Founder and Principal, Lateral Dynamics LLC
      [email protected]
      lateral-dynamics.com

      One tenth of a second on the race track is often the difference between first place, and fourth.

    7. #7
      Join Date
      Sep 2016
      Location
      Atlanta
      Posts
      43
      Country Flag: United States
      Yes you do need steering arms to calculate rack ratio. That has been my issue with most all of the "rack manufactures" flaming river, DSE, ect,ect they claim a ratio but wont give you the gain per revolution. One of the few rack mfg that you can pick you ratio is Woodward. but it's 4k. OUCH !! So In my build I need 10:1 best could live with 12:1 that puts me down to a 4.156 long steering arm to make that happen with an off the shelf rack. Not ideal, and with 345 front tires that also gets you playing games with steering arm position for bump steer and ackerman angle not to mention hydraulic load on the rack. The other option that you can use is a steering quickener. I lot of my off road customers run these on their trucks. I am struggling with these issues myself right now.

    8. #8
      Join Date
      Jul 2020
      Posts
      24
      Thanks for the insight guys.

      I’ll keep all this in mind when planning this part of my build.
      Rick
      65 Fastback Mustang
      89 Daytona Shelby
      18 Charger R/T Superbee