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Thread: 84-84 gearbox legal in ITA?

  1. #1
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    Default 84-84 gearbox legal in ITA?

    the only ratios listed in the GCR are for the 79-83 box, but the 84-85 is a legal car for ITA, so its gearbox should be legal as well. anyone know for sure?

    ------------------
    Russ Marshall
    #31 IT-7

  2. #2
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    Russ:
    As long as it comes out of a 12A car. The transmission out of a 84-85 GSL-SE is not legal in ITA.

    The repair manuals (Hayes) only give the gear ratio for the 1983 year model. So that is the one I use. That just makes it easier if I should need to get teched. (which I have)

    If you would want to run a 84-85 trans you can get a copy of the factory spec sheet from Mazda and provide it to Tech if you should ever need it.

    Rick Thompson #99 IT7

  3. #3
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    Default

    Also, since I believe the 84-85 is on a different spec line than the 79-83, you could not use it in a 79-83. Update/backdate only works if the vehicles are on the same spec line.

    ------------------
    Bill
    Planet 6 Racing
    bill (at) planet6racing (dot) com

  4. #4
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    Originally posted by planet6racing:
    Also, since I believe the 84-85 is on a different spec line than the 79-83, you could not use it in a 79-83. Update/backdate only works if the vehicles are on the same spec line.
    ???? That's the first I've heard of that. I'll have to check that out when I get home, but I 99% sure that that is incorrect. The 84-85 GSL SE is in ITS (FI, 13b car with different suspension), but the 84-5 GSL should be on the same spec line as 79-83.



    ------------------
    Scott Rhea
    It's not what you build...
    it's how you build it

    Izzy's Custom Cages

  5. #5
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    Hey Saturn guy, when all else fails please read the ITCS Spec line. Mazda RX-7 (12A) (79 -85)

    You ain't preparing to protest your 1st gen RX-7 racing pals at the Farm are ya Saturn guy.

    Have Fun
    David

    ps: Ben, watch em.........

  6. #6
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    Ha Ha! Made you look!!

    Sorry! I was going by "memory." Obviously that didn't work!!!

    ------------------
    Bill
    Planet 6 Racing
    bill (at) planet6racing (dot) com

    [This message has been edited by planet6racing (edited September 14, 2004).]

  7. #7
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    Default

    Thats what I figured, I just thought it was odd when the ratios were not in the ITCS. I may just throw the 83 tranny in anyway just to avoid any issues.

    thanks guys!

    ------------------
    Russ Marshall
    #31 IT-7

  8. #8
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    David, you and I will have to park our cars in a covered sealed off tent. As far as I know my car is legal, but i'm sure plastic car boy could find something if he looked hard enough. I may or may not be using an electric fence around my paddock space, just to reserve it you know.

  9. #9
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    Ben, do ya think Saturn guy knows what a street port sounds like ?

    Have Fun
    David

  10. #10
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    No, but I know what a lollipop looks like!

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    Bill
    Planet 6 Racing
    bill (at) planet6racing (dot) com

  11. #11
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    Russ,

    Sounds like you got it, but just in case.

    79-85 12A(ITA)

    1st 3.674
    2nd 2.217
    3rd 1.432
    4th 1.000
    5th .825

    84-85 13B'(ITS)

    1st 3.622
    2nd 2.186
    3rd 1.419
    4th 1.000
    5th .76

    The 2nd-4th splits are marginally closer in the 13B, but a proper racing rearend is going to dictate the use of 5th at some tracks. That being the case, I wouldn't want to use the 13B ratios even if it were legal.

    ------------------
    Daryl DeArman

  12. #12
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    well, there is a different set of gears in the 84-85 box (with a 12a, NOT the gsl-se 13b)

    they are:
    3.622
    2.186
    1.419
    1.000
    0.807

    I have been running this box for a while only because it was the only 12a tranny I had that was not destroyed, however i just broke the 4th gear synchro in it so i was just wondering if it was legal or not to decide what box to rebuild. I would assume update/backdate would make it legal (even swapping parts between this box and the 79-83 box should be legal).

    btw i eventually decided the 79-83 has slightly better ratios for my powerband, so thats the one im building...

    [This message has been edited by crushed (edited September 17, 2004).]

  13. #13
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    Can someone with a Mazda Rx7 79-95 FSM verify the availability of the other ratios?
    If so, should be as simple as a letter with supporting documentation.

    ALL of my Mazda literature went with the sale of the last Rx7.

    My unofficial internet search only shows two manual transmission ratios available in the rx7 from 79-85: 1 for the 12A and 1 for the 13B.

    ------------------
    Daryl DeArman

  14. #14
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    http://www.wankel.net/~krwright/files/1985...anual_trans.pdf

    that is the 85 FSM, but there is a type-o, they have the 13b 5th and 12a 5th swapped. DOH!

  15. #15
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    Crushed,

    should be as easy as writing a letter requesting a correction.

  16. #16
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    Originally posted by crushed:
    I would assume update/backdate would make it legal (even swapping parts between this box and the 79-83 box should be legal).


    [This message has been edited by crushed (edited September 17, 2004).]
    Ummm...IF you are suggesting that you could take a gear from one box and others from the other box, I disagree.

    The update/backdate rule allows assemblies, not the interchange of parts within the assemblies.

    Now the definition of "assemblies" can be strained, but this one is clear...a transmission assembly includes the gears!

    I quote:

    "Any .....component shall be substituted as a complete assembly (engine longblock, transmission/transaxle....). No interchange of parts between assemblies is permitted...."

    Seems clear to me. Am I missing something?



    ------------------
    Jake Gulick
    CarriageHouse Motorsports
    ITA 57 RX-7
    New England Region
    [email protected]

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