Bruno drive

Discussion in 'PSI Superchargers Tech Questions' started by largeeng, Apr 23, 2017.

  1. largeeng

    largeeng New Member

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    Hi, I am looking advice/info on Bruno drives. We are running one behind a blown hemi in UK Pro mod series ( basically roots blown NHRA legal). It is an older version with the smaller pump (GM?). We've been running into issues with leakage which I think is 99% down to excessive run out of the converter snout. We have a new flexplate on order and the converter (older Neale Chance bolt together) is going out for repair to ensure it is running true.
    What are the thoughts on this set up, I know most would go with the heavier duty Bruno now. Are we going to be fighting this combo as regards leaks/reliability. Are there mods we can make to improve such.
    The car has potential but the leaks are holding us back

    thanks

    Steve
     
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  2. Mike Canter

    Mike Canter Top Dragster
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    Steve, I would check the runout on the converter after you install the flexplate. It would be very unusual for a Chance converter to have runout. Also change the bushing and seal in the Bruno. If you had runout then both the seal and bushing would be bad. If you have excessive runout then the bushing going into the Bruno pump would show it.
     
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  3. mogenss

    mogenss Member

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    Hi, I go through this list every time I put the bruno back on
    1) Check that crank face and flex plate is clean and nice.
    2) check flexplate run out
    3) bolt the converter up and check converter snout run out (should be +- 0.002 in or so)
    3) check the bell centering (should be less than +- 0.005 in)

    That fixed my problems.
     
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  4. largeeng

    largeeng New Member

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    Thanks Mike and mogenss for the replies. We have been replacing the seal and the bush frequently to no avail. Hopefully we are on top of the problem.
    Is it possible that the pressed steel rear cover on the converter has some distortion? We were able to have a look at a PTC converter for the HD Bruno setup and that looked like it had a much beefier centre plate compared to our old Neale Chance. We will check this out anyway.
    What clearance should we have on the pump bush to converter snout?
    Also what pump pressure should we have as a starting point and how much of an effect does varying the pressure make ie can this be used as a tuning tool for track conditions or set it and leave it alone
    Lastly can our Bruno be upgraded to the bigger pump and shaft, or do we need to change it all out?

    Thanks once again for taking the time to answer these questions

    Steve
     
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  5. Mike Canter

    Mike Canter Top Dragster
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    Steve I can call Bruno Monday and ask if it can be easily updated. A good starting point on pressure is 150-160 psi when the engine is steady at around 3000 rpm or high enough in rpm to get a steady needle reading. I can also ask Bruno about clearances
     
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  6. mogenss

    mogenss Member

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    I changed mine from the 1 in input shaft to the 1.25 in and the parts needed are: input shaft and drum, pump, pump support. You have to machine the housing to accept the new bolt pattern in the pump.

    It is not to complicated !
     
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  7. largeeng

    largeeng New Member

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    Thanks again Mike, our next race is in about 5 weeks, I'll post up what we find and how we get on

    Steve
     
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  8. largeeng

    largeeng New Member

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    Update. We've had a couple of meetings since I last posted and we seem to have resolved leak problems. We ended up changing out the flex plate, had a new snout on converter and realigned the bellhousing. So far so good.
    Thanks for the advice and surely won't be my last post on here
     
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