Bruno assitance

Discussion in 'PSI Superchargers Tech Questions' started by OwnBlock, Feb 17, 2020.

  1. OwnBlock

    OwnBlock Member

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    bruno brake clamps like no tomorrow. converter drives the car from the get go - very hard to hold it on the brakes.

    set up at idle with 160 psi on the bruno
     
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  2. lucky devil

    lucky devil Member

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    its quite possible that the pressure is too high.... Whats the rest of the combination ? Convertor , motor , power adder , gear ratios ?
     
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  3. Mike Canter

    Mike Canter Top Dragster
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    When you adjust the pressure are you in neutral and increasing the engine rpm to around 3000 so the needle settles down?
    What fluid are you using?
    Have you checked the condition of the band and is it adjusted correctly?
    Is your air pressure correct?
    Are you using a Grid and if so are you pulling out timing when up on the converter?
     
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  4. OwnBlock

    OwnBlock Member

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    lucky devil: hemi, chance, psiD. b&j 3 speed

    mike. rpm I read the 160 pressue at was 2-2200. adjusted in and out appeared to not change. came up as I added more 10 wt hydraulic fluid. been running this wt for years.

    pulled the dual pressure unit apart found there was some co2 rusty scale in the Tee valves, cleaned this up checked pressure only after this action. read perfect at 250 lb to the bruno

    I had converter checked locally as this is the 2nd time hard to hold like this since we fitted a steel stator. we have rebuilt the converter and never had an issue prior to this when running the aluminum stator, changed as ali one mushroomed really bad

    its possibly now 1 of is 2 things: 1 air pressure too high and oil pressure too much.

    1st burnout after the converter was checked out it was back to normal - i was able to hold car on wheel brakes. after that it was hard as to hold.

    Just drained bruno oil. not smelly = not burnt

    no grid. it failed to allow the engine to start so run without it - havent used it for > 4 years now
     
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    Last edited: Mar 7, 2020
  5. Mike Canter

    Mike Canter Top Dragster
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    A couple of things. First if the transmission fluid has friction modifiers in it then it can be too slick. I would say that 90% of the NHRA and other top Promods use the Redline lightweight ATF. We could get 30 runs out of it. Maybe you should try some. The other thing is if your car has moved several times on the Transbrake then the band might be gone. You could change that with the new fluid. I know racers with Bruno’s and screw blowers and not creeping on the brake but they are all pulling out timing when on the brake.
     
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  6. OwnBlock

    OwnBlock Member

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    Just to clarify -the transbrake has never slipped, the last 2 outings ( since grinding the drum and fitting a new band ) all of a sudden it now works too good. when applied it locks on and stops the car in its tracks, I mean - with a jolt, release the button and its go again. Its like the transbrake is too perfect.

    I do like your views on Redline. And replace the grid.

    Im yet to test transbrake since cleaning out the co2 dual valve unit
     
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  7. Mike Canter

    Mike Canter Top Dragster
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    I am confused then if you say it is hard to hold on the brakes but the Transbrake doesn’t slip. If you feel a jolt then you are applying the TB when the car is still moving which will burn the band real fast.
     
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  8. OwnBlock

    OwnBlock Member

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    TB locks car solid - TB applied to shift the lever for forward / reverse. So no speed when this action took place. Band is perfect.

    With TB off holding car on wheel brakes as I come into stage or backing back is very hard, car is driving like the converter has absolutely no slippage. Converter was adjusted recently which worked only once after. next pass it went back to difficult to hold on wheel brakes.

    When I found it difficult to hold on WB I flashed on the TB. This is when I discovered car jolt to a sudden stop.

    Hope this helps
     
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  9. Winr

    Winr New Member

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    Sounds like too much pressure to the Converter... Whats Bruno say?
     
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  10. rb0804

    rb0804 Active Member

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    Your saying the converter appears to be too tight like when your foots on the brakes and about to pull into the lights? You also said the converter has been worked on recently. Is it possible the spray (diode) went in the wrong way? That will tighten a converter waaaayyyy up. A broken sprag (diode) will tighten the converter up also.
     
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  11. OwnBlock

    OwnBlock Member

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    rb0804 this makes sense, as this has only happened since switching out the aluminium stator for a steel one.
     
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