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  • Dogleg versus standard

    What are the main difference's in the close ratio tranny and the standard one. Also what are the advantage's to having the close ratio?

  • #2
    from what I know the close ratio is a dog-leg, with first gear down and to the left, all the gears are lower and 5th is a 1:1. It was meant to work with the Euro 3.15 rear end and does not work well with the US 4.10.

    Close ratio: 3.72 (1st), 2.40 (2nd), 1.77 (3rd), 1.26 (4th), 1:1 (5th), 4.23 (R).

    US box: 3.83 (1st), 2.20 (2nd), 1.40 (3rd), 1:1 (4th), 0.81 (5th)

    Hope this helps
    "It is needless to say that self-propelling vehicles, like other machines, will never do as much for one who does not understand them as for one who does."

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    • #3
      Fist gear is really tall and the rest are close, so when you shift, the car will stay in the power band better.

      While I feel it's not faster for 0-60 times, it's better for driving around, I can pull in 5th, and first I can get on it with out tire spin.


      The trans totally transforms the feel of the car, and just makes the car different.

      On a stock 2.3 I think it is a waste, on a built 2.5 is it a need mod to be able to take off!!

      Do not click
      At least it's German

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      • #4
        Certainly a must-have gearbox, the close top-4 gearing is invaluable.. nothing beats E30 gearbox feel either.
        Alex McHenry

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        • #5
          One downside is the cost of repair parts for the 265 c/r. Very expensive stuff.

          318is 2litre

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          • #6
            Originally posted by AlexMc
            Certainly a must-have gearbox, the close top-4 gearing is invaluable.. nothing beats E30 gearbox feel either.
            With your torque it's very much needed!!

            It would be fun to accaully take off in 1st instead of wheel spin threw 1st!

            Do not click
            At least it's German

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            • #7
              Re: Dogleg versus standard

              Originally posted by kmicinski
              What are the main difference's in the close ratio tranny and the standard one. Also what are the advantage's to having the close ratio?
              On the "close ratio" 1-2-3 are closer together than the US OD trans. Actually the 3-4-5 gears are *further* apart than the OD trans. For a street car, the dogleg is nicer...(of course the Alpina is the best trans for all but pure race cars which the GrA is the best). Anyway, the dogleg is nicer on a street car because of the 1-2-3 shifts.

              On the track, an OD trans with a 4.68 rear will be a bit faster than the dogleg (with a 3.73, 3.91 or 4.1). On the track, you need at least a 3.73 with the dogleg (probably a 3.91 and how high you go is dependent on your rev limit...if you rev to 8200 then a 4.1 is pretty nice). A US OD will be faster on the track with a 4.1 than a CR with a 3.15 or 3.25 rear, for most engines.

              On your average Stage2 headed 2.5L a US OD suffers with a 4.45, you need a 4.1, 4.27 or 4.68 to be optimal. For some reason the 4.45 makes the shift points sub optimal.

              But, which trans is better for you cannot be determined without having your the torque data from your engine every 100 rpms and plotting the wheel torque with all the different combinations.

              The best option though is the Alpina (for cars that see the street) or the GrA for racecars.

              Andrew

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              • #8
                The Alpina gearing is really amazing... For occassinal street, autox, track it is perfect. If you have a trailered race car the Grp. A is best with its 2.33 1st gear but 3-4-5 is just about the same as the alpina (3rd is a little shorter on the Alpina however). The Grp. A and Alpina gears make a high output narrower powerband motor much more usuable than the wider spacing of the OD and Euro CR trans.

                Here is a graph I made comparing ratios for those interested:
                http://www.bayareamotorsport.com/~jj...ox/Gearing.jpg
                Jeff J.
                1990 E30 M3

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                • #9
                  How would one go about finding an Alpina gearbox?
                  1988 M3
                  2012 335is
                  1993 Civic Si

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                  • #10
                    Well heres my opnion....

                    Alpine runner...i run the CR tranny with a 4.10 and its brilliant...it works plenty well...

                    I think the CR tranny would be kind of lost if you put a 3.15 or 3.25 in it....a 3.46 at minimum would be best...3.64 and 3.73 being even better for street/track driving...the 4.10 is a little much for the street...but as long as you dont do a lot of high way miles...its ok...

                    AndrewT is pretty accurate in what he posted...

                    It is by far the best mod i've done to my car yet....i love it...

                    Mike- The CR tranny is not wasted at all on a 2.3L.....its great for any car...if anyhting i think its better for a 2.3L thats not making as much power(especially if you are going to run a 3.64 or greater diff)....
                    0-60 times probably arent improved with my setup either as i have to go into 3rd....but i think if i could get a good launch in 2nd with enough wheel spin not to bog down my 0-60 times could be pretty damn good....not that i care about that...or am i going to waste my new clutch launching in 2nd for 0-60 times

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                    • #11
                      I have a CR w/ a 3.25, although first gear is soooo low, 2-3-4 feel fantastic. My car feels like it pulls better, plus I can downshift into first now. I cannot believe euro models got a CR w/ a 3.25 cause I have a 2.5L, and I feel to run this setup, you need even more torque.... Which makes me think why the Sport Evo has a 3.15!?!

                      I'm not sure if i'm going to maintain my setup or go with a 3.46 or 3.64... I think 3.73 is too tall for what I want.

                      90 Sterling 2.5L E30///M3 lifer
                      97 Porsche Carrera S
                      13 Audi S6
                      SOLD 03 Audi RS6 daily
                      GONE 88 E28///M5 project

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                      • #12
                        Re: Re: Dogleg versus standard

                        Originally posted by AndrewT
                        On the "close ratio" 1-2-3 are closer together than the US OD trans. Actually the 3-4-5 gears are *further* apart than the OD trans. For a street car, the dogleg is nicer...(of course the Alpina is the best trans for all but pure race cars which the GrA is the best). Anyway, the dogleg is nicer on a street car because of the 1-2-3 shifts.

                        Andrew, where you been?

                        Anyways, I think both you and Mike are right. Mike was refering to absolute gearing numbers comparing the two trannies, while Andrew T was talking about the delta between gearing within each respective tranny.

                        90 Sterling 2.5L E30///M3 lifer
                        97 Porsche Carrera S
                        13 Audi S6
                        SOLD 03 Audi RS6 daily
                        GONE 88 E28///M5 project

                        Comment


                        • #13
                          having driven both OD and CR transmissions, I think the the CR works better
                          at the track. On tight 40 mph corners you can actually still shift down into 1st gear.

                          the diff ratio doesnt effect the gearing spread. you select diff ratio for
                          application.

                          when I drove the CR with 4.10 rear diff, it topped out around 230 kmh at 8400 rpm.
                          (I have the rev limiter at 8500). Its too short for high speed stuff.

                          PS: actual the 3 to 4th gear shift is the same on both
                          boxes, meaning the spread is the same.
                          its the 4 to 5th shift that is slightly shorter on the
                          OD box (23.5% difference as opposed to 26% difference).
                          So you lose 2.5% on that shift to the OD box, but
                          the CR box will pull the higher top end, diff ratio being
                          equal.

                          John
                          Last edited by John; 04-06-2004, 08:40 AM.

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                          • #14
                            Re: Re: Re: Dogleg versus standard

                            Originally posted by SeattleE30///M3
                            Andrew, where you been?
                            Somebody drug up a 2 month old thread.

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