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Automotive Ford Toploader Conversion To Top Gear Only

  1. Jan 14, 2012 #1
    while i was typing title i think i just thought of answer.
    why take out the other gears?
    other gears would be good for moving car around
    and maybe try leaving line in 2nd.
    i'll press on.
    can i keep top gear ( direct drive 1:1 ) and take out the rest?
    also keep neutral for safety.

    Have A Nice Day!
  2. jcsd
  3. Jan 15, 2012 #2

    Ranger Mike

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    many super late models run 2 peed trans to reduce rotating weight and overall weight..need 2nd gear.the final l drive ration on short track is tall..6.17 and the like...so second gets you out of the pits and high gear is straight thru
    many use the three speed man trans to cut down even more speed..depends on the case and strength of design
  4. Jan 15, 2012 #3
    ranger mike
    oval racers do use 2 speed.
    what about a Drag version of top gear only.
    that would be gear it for speed at end of 1/4 mile.
    then slip clutch to get going.
    the car would be pushed to start line and return lane
    so that's not a reason to put first or second gear back in.
    leave 1 and/or 2 in?

    Have A Nice Day!
  5. Jan 16, 2012 #4

    Ranger Mike

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    you can make a drag car with i,2,3 or four gear trans..it is a matter of the cars weight and the engines RPM power band and torque curve...a small block chevy running between 4 to 8000 rpm will need a lot of gears since it will suffer bottom end torque to launch..a torque monster 440 cid wedge mopar will top out around 6800 rpm and has to be geared accordingly. What you want is a trans package that will permit car launch at minimum clutch slippage and can stay in the rpm sweet spot the longest over the 1/4 mile. You can make a two speed to launch and go the quarter but the rpm range has to be pretty wide.
  6. Jan 16, 2012 #5
    ranger mike
    i'm going by what i've seen in early 60's dragsters.
    it's a bellhousing and then a drive shaft.
    since those units are probably pricey, i figure the
    way to do it is use regular trans with top gear only.

    Have A Nice Day!
  7. Jan 17, 2012 #6
    I think i've figured out why you are asking the question in the other thread.
    Why on earth would you want to do this?

    Dreadful launch (have you ever tried pulling off in top gear).
    Off cam for most of the run.
    Will ruin your clutch.
  8. Jan 17, 2012 #7
    it's big kid science stuff.
    ranger mike pretty much answered question.

    Have A Nice Day!
  9. Jan 17, 2012 #8
    Leave 'em all in, you'll be glad you did!:smile:
  10. Jan 18, 2012 #9
    this is better!:smile:
    on the trail of clutch/direct drive.
    early dragsters have bellhousing and driveshaft, that's it.
    clutch pedal only, no shifter.
    think that might be a Crowerglide inside bellhousing.
    big 3 plate clutch w/adjustable weights for engagement.

    Have A Nice Day!
  11. Jan 18, 2012 #10
    They were designed to be used like this though, a standard box isn't.
    It makes no sense to take something, reduce it's functionality with no positives.

    They key to drag racing is to keep the tyres at traction limited acceleration at all points. (ie max acceleration).

    Which is why
    Is the only sensible thing to do.

    You can always just do a run in top only to see how dreadful it would be. It saves you then having to rebuild the box.
  12. Jan 18, 2012 #11
    the benefits of using the stock bellhousing and trans
    super outweigh making it from scratch.
    i need to save my energy for working that clutch pedal.:smile:

    Have A Nice Day!
  13. Jan 18, 2012 #12
    To give you an idea of how much performance you'd lose:

    1. Slip and slide, one gear only and 120 mph in the 1/4 mile:
    ET 13.88 @ 121.6 mph
    2. Same exact set-up except using all four gears and the same final drive:
    ET 10.28 @ 129.4 mph

    Over 2 1/2 seconds quicker in the 1/4 mile by using all four gears.

    But if that's what you want ...
  14. Jan 19, 2012 #13
    i almost take offense at applying 'slip and slide'
    to this noble effort.
    i like the simplicity of my idea.
    l bring up the rpm's and let the clutch out gradually
    until i can let it out completely.
    then floor it!
    it's just sounding better all the time.:smile:
    fyi: this is econo rail, putting a new clutch disk in is a cinch.

    Have A Nice Day!
  15. Jan 19, 2012 #14
    I'm hinting strongly that if you are set on using only one or two gears you should consider using a (slip 'n slide) Powerglide instead; at least with a torque converter you get multiplication of the torque to help compensate for the lack of gearing.

    Slipper clutches are used when the power available is too much for the tires to hold. An econorail doesn't have that kind of power unless you lower the traction available by using very hard and narrow tires. Either way it will be slower than doing it in the more conventional way. That's why I posted the results from a 1/4 mile simulator, to show you how much slower it would be.

    I'm not dissing your project, just trying to save you a ton of work to get a mediocre result.
  16. Jan 19, 2012 #15
    i think i answered my own question by saying
    the car can be pushed to starting line and
    back down.
    so top gear only.
    i'd like to know how to remove first and second
    gear from a Ford Toploader 3 speed.
    plus any tips about strengthening it while i'm in there.

    Have A Nice Day!

    "It's what you learn after you know it all that counts." ~ Harry S Truman
  17. Jan 20, 2012 #16
    1. You want to try this, fair enough.
    It's totally counter intuative for performance.

    2. What do you expect to gain by removing the gears?

    3. Have you done a run in top only yet?
    Doesn't it make more sense, to try that out before stipping the box.
  18. Jan 20, 2012 #17
    i need to see one of these original setups.
    i think it's one shaft from the clutch to
    the rear end, and it's plenty strong.
    going the stock trans & clutch, driveshaft route
    has these advantages:
    1 has the shaft
    2 has case to hold the shaft
    3 shaft has clutch splines
    4 shaft has u-joint
    i'd have to 'nurse it' down the track
    BUT it would work the same way as original's.
    launch, run and that's it!:smile:

    Have A Nice Day!
  19. Jan 20, 2012 #18
    You aren't actually applying any logical thought to this set up. Your whole thought process seems to run along the lines of, it's sort of looks the same therefore will run the same. I can pretty much agree that the drag car would have been running a torque converter, not a clutch. Which makes a whole world of difference in the launch.

    You've also not answered the question as to why you feel it's necessary for you to remove two of the gears. Which serves no useful function over leaving them in the box and just running in a single gear.
  20. Jan 21, 2012 #19
    'Power from the early Hemi is channeled to the 3:90 cogged 8/34 Chrysler, Detroit Locker, diff via a Hayes dual disc clutch coupled to a Lenco direct drive "In and Out" box.'
    no torque converter there!
    i'm building a Ford Toploader Direct Drive In-Out box.
    leaving the 1-2 gears out saves weight.
    my little Ford 292 needs all the help it can get!:smile:

    Have A Nice Day!
  21. Jan 21, 2012 #20
    Fixed it for you!
  22. Jan 22, 2012 #21
    i got the word on this.
    the way they used to do it was,
    yes, no trans at all, they would sidestep the clutch
    and just go down the track burning the tires until
    they caught up and quit spinning.
    i thought i was supposed to ride the clutch out
    until i could get traction.
    i may still build a direct drive. i'll ponder it some more.:smile:

    Have A Nice Day!

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    Last edited: Jan 22, 2012
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