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Projects Front engine dragster-Chassis Research 1958 -"Moon Rocket"

Discussion in 'Traditional Hot Rods' started by TheTumbleweeds, Jul 18, 2013.

  1. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    I found the ultimate head brake cylinder for my dragster! I dont know why the Picture came upsidedown? But anyways, I Can Mount a brakebar directly to the cylinder, I LOVE it DSC_3129.jpg
     
  2. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    I belive chevy truck 55-59?
     
  3. volvobrynk
    Joined: Jan 30, 2011
    Posts: 3,587

    volvobrynk
    Member
    from Denmark

    That's a early Chevy single circuit truck master, fits most Chevy AD and TF, 1949-59.

    The are mostly the same.
    Maybe @squirrel knows more or @55sedandelivery
     
  4. loudbang
    Joined: Jul 23, 2013
    Posts: 40,276

    loudbang
    Member

    fixed it for you. :p

    DSC_3129.jpg
     
  5. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Thanks man! :)


    Posted using the Full Custom H.A.M.B. App!
     
  6. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    I found this spool on the e b ay and now I think, is there anything to think of? Like big / small bearings? Screenshot_2015-05-14-20-34-34.png
     
  7. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

  8. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Machined the last piece, now, I need to replace the old endings. DSC_3142.jpg
     
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  9. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    I've been workin a little on the brakehandle, It would be nice in Chrome :) DSC_3205.jpg
     
  10. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

  11. loudbang
    Joined: Jul 23, 2013
    Posts: 40,276

    loudbang
    Member

    Wow you better make sure the brake handle has some over travel stops built in. With it that long as they say you could move the earth or bend your brackets or master cylinder in a hard pull panic stop.
     
  12. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Good point there, maybe build a bracket, so I can adjust the bottom end...

    And I think I need a hard spring to return the brake handle, so it keeps it at place when not braking.
     
  13. dreracecar
    Joined: Aug 27, 2009
    Posts: 3,476

    dreracecar
    Member
    from so-cal

    Does not need "limiters or stops" and as long as the pushrod remains with the MS and there is a return spring inside the bore you are fine.There isnt a Fuel car out there that has any of those.
    there are 2 things that brakes do on the back of a dragster, One is to hold you on the line for the start and the other is to keep you from running into the back of the tow vehical on the way up to the line. If you grab the brake hard at the end of the run the car will start bouncing and you will not slow down.
     
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  14. Dre racer speaks the truth! That's why God made chutes.

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  15. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    True words, and yeah, I need to fit a chute.. I need to research more in chute subject..

    About return spring, I think maybe the brake handle weights a little when racing

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  16. loudbang
    Joined: Jul 23, 2013
    Posts: 40,276

    loudbang
    Member


    Let's look at your premise with logic and laws of physics instead of rhetoric. A couple things things come into play in like I said a PANIC STOP.

    The first thing is muscle memory while put puting around the pits of course there are no major forces involved but one is ALWAYS using that handle to slow or stop the vehicle so your brain and muscles become accustomed to doing those movements. It's just like stepping on the brake pedal in your daily you don't have to stop and think OK how do I stop this car what do I step on. Your body just does it WITHOUT CONSCIOUS THOUGHT because you have done it so many times there is no reason to think about it.

    AND THEN a kid chasing a ball, deer, moose, horse, another vehicle WHATEVER pulls out right in front of you while you are driving at road speeds. What happens? For us mere mortals your body slams on the brake automatically in the few microseconds you have in reaction time BECAUSE THAT IS HOW YOUR BODY RESPONDS TO "STOP THE CAR RIGHT NOW" SIGNAL FROM YOUR BRAIN.

    Maybe some super duper athletes or fuel car drivers can train their brain to ignore muscle memory and remember "DON'T TOUCH THE BRAKE HANDLE" in a panic stop but us normal people can't do that.

    While a State Trooper I investigated over 1000 accidents and the vast majority involved a panic stop situation and NOT ONE driver EVER said "you know it's cool I remembered to pump my brakes while stopping" NOT ONE and we all know that is why ABS systems were developed BECAUSE THE AVERAGE PERSON NEVER REMEMBERS TO PUMP THE BRAKES OR ANYTHING ELSE BEYOND SLAM ON THE BRAKE PEDAL.

    The next thing that needs to be discussed is the length of that handle vs the length of the other end under the fulcrum point. Just using the photo it looks like the low length is 1 1/2 cm while the upper length is 13 cm. Close enough for our non-scientific discussion here. So that is about a 13/1 ratio.

    We all know from our high school physics classes that the longer the upper portion (above the fulcrum point) THE MORE THE FORCE APPLIED THERE EFFECTS THE FORCES ON THE BOTTOM PORTION BY INCREASING EXPONENTIALLY BY THE RATIO.

    Think about it for a moment ....... my skinny 155 lbs body actually bent a genuine HURST rectangular shift handle just by powershifitng in a close race in my youth.

    Now take this build and it's finally done and he is on a high speed run and pops the chute and NOTHING HAPPENS. We all know chutes never fail and or crew members NEVER forget to remove the safety pin:eek: (if you believe that giant one I have a bridge for sale in NYC you might be interested in) So what happens? Now if you are a big time fueler driver you just sit there and wait for it to slow down because one never stops by using the brake handle.

    But if you are a mere mortal like the rest of us your MUSCLE MEMORY takes over while heading for the dirt trap, tree, river, whatever at the far end of the strip and your body, with no conscious thought, pulls that brake handle for all it's worth.

    And that folks is why this particular build needs more metal in those brackets and or a shorter upper lever. The way it stands now I bet I can bend those brackets or blow the master cylinder right out or off using what strength my now 65 year old body can generate with that long handle even while not in panic mode. :rolleyes:
     
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  17. dreracecar
    Joined: Aug 27, 2009
    Posts: 3,476

    dreracecar
    Member
    from so-cal

    You might have investigated 1000's of accidents of cars weighing 3000# and 4 wheel brakes using public roads and hiways at speeds less that 80mph----BUT this is a dragster !!!!! A race car with a single purpose of getting to point A to B as quick as possable for its given class.
    Major differences being--
    Light weight around #1600(with driver)
    2 wheel rear brakes only (no front brakes)
    Run on a single purpose track and for the most part only with one other car at the time.
    Speed estimate for this car should be 140+
    So lets break this down
    Light weight--- its for acceleration and not road holding and most of the bias on the rear (and not the front as most street cars) so front brakes are not effective because of very little front end weight and if there were brakes on the front they would lock up and skid and one would loose steering ability, Boats use rudders to steer, cars need the wheels turning in order to steer. The rear tires are engineered balloons with a traction surface, Very thin sidewall designed to wrap and twist in order to spring and launch under acceleration and when at speed tend to grow in diameter. Given that at most there is only 7# of air in them at the start, at speed since the dia grew bigger there is a pressure loss due to volume increase. Applying the brakes hard at anything above 50mph will cause forces to wrap/wind the tire around the wheel which reduces its dia. and then when the energy is released by the tire un-twisting itself, will spring the tire back to its larger dia, thus catipulting the rear of the car upwards and then starts bouncing. Without the tire on the ground, the brakes are useless and one travels 10 feet in the air to 2 feet with ground contact-- that my freind uses up a lot of real estate quickly. If the tires are locked up while in the air and come down to make contact the the principal of "every action will have an equal and oppisite reaction" applys and the car is on the verge of crashing. Panic stops during being towed around in the pits are not much an issue since speeds are regulated to under 10mph, however I have seen pit accidents before, but that was caused by an extreemly busty young lass and the person riding in the seat of the racecar being distracted and running into the back of the tow car.
    The leverage factor of the hand brake handle might be a little excessive, and more for style but should not cause problems and offers more control of line pressure with minimal force applied verses a foot peddle. Street cars the heal of the foot is on the floor and the ankle is rocked to apply the brakes, Dragsters however the leg is wraped over the RE housing withing tight confinds and the whole leg/foot raised in order to reach the peddle and some muscle accutness is lost. with the leg muscles being stronger then the arm peddle ratios for both are different as the foot brake is 6 to 1 and the hand is 10 to 1 which ballences the differences between the two. Something normally happens when brakes are used, the pads/shoes wear down. If one uses a modern racing caliper then the pucks self adjust and do not retract and the handle/peddle retains the same throw, If drum brakes are used, the only way they adjust for wear is with the E-brake system. so with out a e-brake the throw increrases and one will soon find that that the throw has increased to a point that its backed against the limiters without suffincent line pressure---Opps!

    All of this information is the result of 35+ years of building, driving, racing, and maintaining various forms of racecars with the last 23 years concetrating on dragsters-- from Jrs to Modern Top Fuel
     
  18. loudbang
    Joined: Jul 23, 2013
    Posts: 40,276

    loudbang
    Member

    All that and you said nothing relevant to the discussion. The accident investigations showed MUSCLE MEMORY nothing was said about anything else. Nobody but you mentioned anything about using a foot pedal. You haven't answered the questions. Like how you magically dismiss muscle memory.
     
  19. dreracecar
    Joined: Aug 27, 2009
    Posts: 3,476

    dreracecar
    Member
    from so-cal

    Because raceing is a skill/technique learned and not commonly used in our everyday lives. A guy builds houses everyday and does all the framing with a hammer and is so good that with 2 strikes can drive the nail, does this hundreds times a day, for that has developed "muscle memory", now its the weekend and the wife wants him to hang a couple pictures, Does he let muscle memory take control and drive the brad clean thru the other side or does he use temporary skill/technique to properly set the brad? I'm done here, back to the build
     
  20. SimonSez
    Joined: Jul 1, 2001
    Posts: 1,637

    SimonSez
    Member

    Using info from the Mark Williams web site, that setup looks like the ratio is in the ballpark for a hand-brake on a dragster ...

    http://www.markwilliams.com/braketech.aspx

    1. Their recommended pressure target is 1200 PSI.
    2. Their recommended force for a hand brake lever is 75-100 lbs
    3. Google says that the 55-59 Chevy truck master cylinder is 1 1/8 bore

    So using the pedal ratio calculator on the above link it says the ratio required to get 1200 psi from 100 lbs force with that master cylinder is 11.88 to 1.

    Roughly scaling the pedal ratio from the side-on picture above, I got 11 to 1 so it is pretty much on the money.
     
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  21. saltflats
    Joined: Aug 14, 2007
    Posts: 12,592

    saltflats
    Member
    from Missouri

    I truly hope that when he gets it going the only thing on his mind will be the loud peddle.
    So what are the plans for the headers?
    When ever I get the chance to get to mine it will have a pontiac and weed burners.
     
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  22. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    About the brake handle bar, I was thinking of afoot pedal length and you have a pretty strong muscle in the leg, and then Change to arm pulling difference, and needed some longer bar. And lucky this has the style I like. Its getting fully polished and going for Chrome. The brackets will hold, im pretty sure when Im done with it ;-)

    And for the headers, Im lovin the straight back type, and finnish of Close to the piecrust slicks tire! :-D

    But I think I build the pipes in the End of whole build, then I see what fits or not.
     
  23. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Something like these (not my Picture, loan from a thread on HAMB)
    DSCN4563.jpeg
     
  24. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Im trying to figure out what sollution I should have for shifter to transmission..
    Do you have some advice on shifter?

    Shifter for powerglide
     
  25. dreracecar
    Joined: Aug 27, 2009
    Posts: 3,476

    dreracecar
    Member
    from so-cal

    My preference has been towards a B&M ratchet mounted to the trans and then run rods/levers back to the rear end housing. Dead space between the legs anyway and does not interfier with the brake handle. If you mounted it on the left side you would wind up swaping hands for the shift. Left hand on the wheel and right hand on the brake, release the brake and right hand on the wheel, take left hand off wheel to shift. Top end is the same thing. Center shift, your left hand is always on the wheel while the right hand works ALL the controls.

    The peddle on the left is to opperate the trans brake in order to back up
     

    Attached Files:

  26. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Finaly...
    the pin holes was to small for longtime, but now a friend had a tool to make it bigger with correct angle. (haard to find..)

    So from this, I can weld those brackets on the chassie, and connect the front end! And build the holding for the spring
     

    Attached Files:

  27. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Maybe my kids doing the right thing, just jump in the dragster, put a coin in, and go for a ride! :-D DSC_3242.jpg
     
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  28. greybeard360
    Joined: Feb 28, 2008
    Posts: 2,074

    greybeard360
    Member

    E brake does not do anything to adjust the brakes...... Otherwise the self adjusters on the front brakes would never work. Each time the brakes are applied it pulls on the cable attached to the adjuster lever and when the shoes wear enough it will have enough movement to turn the adjuster.
     
  29. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    Okey, I have talked to a local workshop, to bend those last pipes, to complete my chassi. So I gave my green swing tubings, as a "drawing", ..

    so very soon, I can go on with the chassi, and start look at the cockpit :)
     
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  30. TheTumbleweeds
    Joined: Jul 29, 2010
    Posts: 539

    TheTumbleweeds
    Member
    from Sweden

    I got my tubes yesterday :)
    Total 10 pcs, 4 bended, 6 straight ones..

    So happy right now! DSC_3543.jpg DSC_3544.jpg
     
    volvobrynk likes this.

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