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    Results 1 to 10 of 10
    1. #1
      Join Date
      Apr 2015
      Posts
      13
      Country Flag: United States

      Which Magnum Ratio?

      I want to buy a new Magnum 6 speed for my 69 Camaro, my car will be a street driven driver, which ratio would best suit my application? I plan on running a 375-450 hp engine. Thanks

    2. #2
      Join Date
      Sep 2010
      Location
      Orange County, CA
      Posts
      665
      I like the close ratio. But what rear gears are you running?

    3. #3
      Join Date
      Nov 2014
      Posts
      233
      Country Flag: United States
      using the wide ratio magnum in '67 Camaro, 3.50 rear gear, 27" tall rear tire. Works really well on the street and road

    4. #4
      Join Date
      Aug 2016
      Posts
      15
      Dan - I ended up doing the Magnum close ratio 1-4, and wide ratio 5-6 overdrive gears so I could get lower rpm cruising on the freeway, but tighter gears down low for performance driving or track time. I'm building a 70 Camaro running 3.73 rear end with 26.5" tall tire so I didn't want the lower 1st and 2nd gear ratios of the wide ratio has to offer compared to the close ratio 1st and 2nd. The guys at Bowler set me up with this transmission and were great to work with. Since the overdrive gears run on a separate shift rail, you can mix and match with the Magnum. I hope this helps.

    5. #5
      Join Date
      Oct 2014
      Location
      DFW, Texas
      Posts
      422
      Country Flag: United States
      I run the close ratio (0.62 6th) in my Hemi 'Cuda and would definitely do it again. I do not feel that the 0.5 6th is well suited for an old car unless you are running remarkably low gearing [I have 3.91]. The cruise rpm is just too low and it is very easy to generate chassis and exhaust resonance down there if everything isn't just right.

      That ratio 6spd runs through the gears very well and is an excellent match for me.

      1972 Plymouth 'Cuda - Not LS-swapped, 5.7L Hemi [MS3 Gold Box], T56 Magnum 6-speed - 'Cuda Build Page
      1976 Dodge D100 - Warlock
      2016 Subaru WRX - E30 Tune

    6. #6
      Join Date
      Feb 2016
      Location
      Lawrenceville, IL
      Posts
      348
      Country Flag: United States
      Quote Originally Posted by Dan Shook View Post
      I want to buy a new Magnum 6 speed for my 69 Camaro, my car will be a street driven driver, which ratio would best suit my application? I plan on running a 375-450 hp engine. Thanks
      Dan,
      The close ratio is by far the most popular choice for just about everyone, but like Josh stated we can mix and match the OD gears to set you up with the best possible scenario. It really is dependent on your rear gear and tire size though as to what may be the best set up. I consistently see 3.73 gears and 26-27" tires with most of my customers and the close ratio works really well for that set up. I do have a spreadsheet that I can plug your info into and email you the results if you're interested in seeing what the different gear ratios will do for you. [email protected]
      visit us on the web at www.bowlertransmissions.com

    7. #7
      Join Date
      Jan 2014
      Location
      Portsmouth NH
      Posts
      247
      Country Flag: United States
      I am running the close ratio with the 0.8 5th and 0.63 6th. It is perfect with my 3.90 diff gears and the 26.7 rear tires I run. This is in a 69 Camaro with a SBC pushing about 400RWHP.
      1969 Camaro (Small Tyre Restomod/mild Protour) 245/40/18 F, 275/35/18 R, stock frame, full Ridetech suspension, LS engine, T56 Mag, Wilwood Brakes. A driver car.

    8. #8
      Join Date
      Dec 2010
      Location
      Fredericksburg, VA.
      Posts
      3,155
      Country Flag: United States
      I'm also running the close ratio T56 Magnum with a 3.89 rear end gear and 27" tire. It is near perfect IMO.

      Here is Tremec's gear ratio calculator.
      http://tremec.com/calculadora.php
      Steve Hayes
      "Dust Off"
      68 Camaro

      Given sufficient initial acceleration, even pigs can fly!

    9. #9
      Join Date
      Jun 2010
      Location
      Deployed
      Posts
      3,280
      Country Flag: United States
      I suggest a custom gear change for 6th. Get the close ratio and swap out 6th for the .50 ratio. I'm not thrilled with 3.89 gears and the .6x final ratio.
      1970 Camaro/DSE build


      Are you driver enough? Maybe....come on blue!
      https://www.pro-touring.com/threads/...71#post1147371

    10. #10
      Join Date
      Feb 2016
      Location
      Texas
      Posts
      93
      Country Flag: United States
      When making the same decision you are trying to make, I generated a set of curves for different ratios as a function of my tire diameter and rear gearing. Examples of the curves are shown in 2 thumbnails I attached to one of my posts in the link below. Using a similar analysis you can easily evaluate the road speed/rpm relationship for your car and the type of driving you will be doing and what rpm's your car likes to run at for various speeds.

      http://www.camaros.net/forums/27-tra...version-2.html







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