GS455 Stage 1 Turbo 400 not kicking down

Discussion in 'The "Juice Box"' started by OZGS455, Jul 8, 2018.

  1. OZGS455

    OZGS455 Oh what a wonderful day!

    well yes I was thinking of a Gear Vendors for it but now I know the car hasnt got one then Ill get the 200 R4 set up properly.
    Id like to track down the Turbo 400 though as it adds to the cars originality if its ever sold.
    Doubt thatll ever happen though:)
     
  2. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    The correct THM 400 in 1971 can be either a BB or OW.
     
  3. TexasT

    TexasT Texas, where are you from

    I doubt it is a gn brf vb if I doesn't downshift. The more performance oriented vb will jump from 4 to 2 pretty easily and if you are at a low enough speed it will go to 1. Check the tag on the pass tail on it. And if you end up dropping the pan look for the paint mark on the vb . Many are washed off when overhauled and this makes identification much more difficult.
    Look into the tv cable and how it should be adjusted as when it isn't right low line pressure will hurt clutches by letting them slip.
    I think one of the biggest misunderstanding on a 2004r is that they are all the same, and people try to mix and match the vb and governors. This creates all kinds of shifting issues. The vb and gov is a matched set from the factory so they need to be kept together to avoid problems.
     
    Last edited: Jul 8, 2018
  4. HeavensDevil

    HeavensDevil Well-Known Member

    Black beauty!
    I never see 70-72s like ours around. Went to a massive cars and coffee in Sydney yesterday. Out of a sea of cars only 3 Buicks; riviera on bags, a 66 lark vert, and my heap of rubbish.
    Enjoy it, maybe Ill see ya out there one day...
     
  5. OZGS455

    OZGS455 Oh what a wonderful day!

    Im up on the sunny Gold Coast mate, couldnt get outta Sydney quick enough, ..so yours is black too looking at the thumbnail pic
    Ive contacted her previous owner and he tells me the guy in Tassie who imported her had the TH400 Buick trans swapped back in.
    For originality I guess...Ill try emailing him later and see.
    Least I dont need to track it down and get it back and my Beloved Buick it back entire again
    May look at the Gear Vendors option but, a few guys in our club are running them, one behind a fairly stout Hemi, with no dramas.
    Oil filters in Oz, this has a KN2003 on it now , went to change the oil last night, Id bought a Ryco Z30 but its longer than the KN and may foul the sway bar mount bolts.
    Heard KN's are now chinese and I try to stay away from their stuff.
    Dude from Autobarn just rang me back saying theres no other choice!
    What are you running.
    I know my Victory bike can use anyone of multiple filters, I dont like not having choices in oil filtration.
    Shes using a bit too but I note the engines only done 4000 miles since the forged slugs were fitted so its probly not broken in as they say in the USA , run in as we say.
    My Vic took a good 10,000 to loosen up after I big bored and went to forgies, it likes a bit of oil now too but I do flog the crap out if it once its warmed up, 12.1@111mph so far.
    Its engine is the equivalent to slicing two cylinders off the 455
    Gonna do an oil system flush this morning then change the thin 10-30 supermarket oil and flush agent for some Penrite 15-50 semi-syn diesel oil same as I run in the bike.
    15 should flow enough for Oz conditions cold and the 50 end should take care of the upper xtremes.
    My trans guy just rang and hes gonna call in around lunchtime and check out the kickdown issue.
     
  6. OZGS455

    OZGS455 Oh what a wonderful day!

    Rang Penrite tech line and was reccomended their Vantage Premium Mineral 15-40, has a good zinc package and is within the upper end of the factory parameters.
    Added a flushing agent and let idle for 15 mins and when I drained it ran out quick.
    Ended up buying a KN Gold oil filter ,so all good on the oil front for now.
    Time to get out and drive her as shes only done 3 or 4 thousand since arriving here in 2012, thats criminal!
    We looked at the kickdown switch and theres minimal scope for adjustment so I bent the switch bracket a little to make the throttle pedal contact the switch mechanism better .
    Will road test this arvo.
     
  7. HeavensDevil

    HeavensDevil Well-Known Member

    Mine looks black but its a dark green. Thats funny about Tassie, I imported mine as a personal import while living in Hobart. Was working in a stainless sheet metal shop there. Ended up moving to Armidale and drove the car straight off the boat in Melbourne, 2 day road trip. Living in Sydney now but plan on moving to Newcastle next. I just run 10-30 synthetic castrol and ryco z24 long case filter and dont worry about it but I got a chev with roller cam in there.
    Get her all sorted and she will run as good as she looks!
     
  8. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    So the transmission is the THM400. Has an electric kickdown. The gas pedal switch is adjustable, procedure in the Chassis manual (which you should order if you don't already have one). One side of the switch has 12 volts anytime the ignition is on, the other side goes to the contact on the driver's side of the transmission. Check for the 12 volts at the switch, then check the switch with an ohmmeter. Then check at the transmission for 12 volts when you activate the switch by hand. There is a downshift solenoid inside of the pan that you can hear click when it is activated. You can apply 12 volts directly from the battery to the contact and listen for the click. Do you get a kickdown now?
     
  9. OZGS455

    OZGS455 Oh what a wonderful day!

    thanks Larry
    ran 12v to the trans first and got a click.
    no power at the wire into the switch
    sound system fuse in radio fuse panel was blown (prefer the stereo glasspacks myself)
    blown fuse was a 20A !.. I fitted a 10A fuse, turned ign on and got power at the wire into the switch
    radio turned on and fuse blew and lost power to switch wire.
    disconnected plug on back of sound system (modern Sony head inside a Buick 8 Track casing)
    fitted a 15 A fuse and stuck my testlight probe into power side of trans plug wire, got a very weak glow from testlight, tried to jam throttle wide open with a brick but didnt work so rang a friend to come stomp on the gas pedal...still only a faint glow.
    My multimeter isnt working , needs a battery, and not sure how to check the switch anyway but I feel fairly sure that its faulty.
    The kickdown switch looks a lot like a common Holden Commodore item (late model GM product here)
    Gonna take it out and match it up with a local one tomorrow.
    Went for a testdrive anyway cos cruising in the Buick is just so addictive and a joy to feel the bridled power underfoot....So much grunt thge kickdown is irrelevant when light throttle cruising.
    Hope to have good news tomorrow.
     
  10. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    This is what the gas pedal switch looks like,

    https://www.ebay.com/itm/1969-77-GM...056840&hash=item3f517a7842:g:L1AAAOSwnbZYGMo9

    They don't go bad very often.

    It sounds like you need to carefully look at the original radio wiring connection. You probably have a direct short (bare wire somewhere) if it is blowing fuses. The Power window Relay, and mirror map lamp are on the same fuse.

    BTW, you don't need to touch the gas pedal to activate the switch, just reach up there and slide it with your finger. It attaches to the gas pedal bracket with one bolt. To adjust the switch, see below. Push hard on the switch in the direction "A". The plunger will bottom out. Then floor the gas pedal.

    DetentSwitchAdj.jpg
     
    Last edited: Jul 11, 2018
  11. OZGS455

    OZGS455 Oh what a wonderful day!

    Thanks Larry, Ill get onto it today,
    My car is manual windows ,which I prefer really, mirror map lamp?
    Dunno if I got one of them..option?
    As for light throttle kickdown, I presume thats regulated by vacuum?...not that it really needs to downshift on part throttle with the immense torque.
    Also gotta track down your info on spark timing and read up good on that.
    Got a bit over a week before the Muscle Car club Im in have the dragstrip booked for 90 minute session.
    The car came with an extra set of blingy wheels 20x10 with ultra low profile 275 tyres so Im thinking of bolting those on the back for the strip,
    Im not a fan if modern bling wheels on classic cars but these sorta suit the Buick, theyre reminiscent of the 'daisy' wheel in some respects I think.
    Anyway the trans is the focus today.
    And getting keys cut for my bike, misplaced my one and only key to my Victory and in spite of major searching cannot find it.
    Some pix, showing wheels, and
    Prime US Muscle on 2 and 4 wheels!
    20180627_154651.jpg 20180709_121534.jpg Screenshot_20180627-093526_Chrome.jpg 20180709_121551.jpg
     
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  12. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    Two suggestions if you are going to take it down the track, one, get some leaded race fuel in the tank, preferably 110 or higher. If the engine detonates at WOT, you don't hear it, and you stay in it, you WILL hurt the motor.

    Two, get/borrow some sticky tires, drag radials, or slicks. If you try to launch the car on those rubber band tires, it will be an exercise in futility/frustration. There is no way to hook the car without good tires.
     
  13. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

  14. OZGS455

    OZGS455 Oh what a wonderful day!

    Ill try for the racegas, other option to take some timing out of it?
    Kickdown switch, one I took out has a diode or resistor or something soldered onto it, on left in pic.
    Got one on right from mates boneyard its off an Aussie GM product ,looks same except for doide thats mystery anyway.
    Just got another 9v battery for my multimeter that I dont know how to use
    Update..watched youtube and then used multimeter to test switch , one I took out had .7 when switch activated.
    Replacement had zero :)
    Now to fit and adjust.
    Mate I got good switch off reckons if I pull dud switch apart and clean contacts inside it may come good.
    That doides a mystery but?
     

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    Last edited: Jul 11, 2018
  15. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    That looks like a resistor to me, which would explain your meter reading:)
     
  16. OZGS455

    OZGS455 Oh what a wonderful day!

    Local boat mechanic a few sheds down from my workshop reckons a zero reading in both switch positions is not good so the used replacement is still on my bench and the original back in there...adjusted as you said.
    Went for a test and when I floored it all hell broke loose!
    She snarled like an angry tiger on heat, lifted her nose, and motorvated big time!
    Gotta chase up a coupla mates that race and see if I can source some Avgas...My local tyre man concurred with you on the ultra low profile 20x10s and Im on the hunt for a pair of wide steelies I can put on out at the track with drag radials on them.
    Ill try and get in to see my old school tuner and get him to set the dissy up to the specs in that link and make sure the carbs set up right.
    I think it has the standard 720 vac sec? Is that what they have factory?
     
  17. OZGS455

    OZGS455 Oh what a wonderful day!

    Just had a quick read of your timing thread, the 1st bit not the 35 pages!
    You talk of 110 octane, I know my Victory runs your 91 which is same as our 98 (same octane but different way of measuring) without hijacking my own thread, Im thinking aloud if Aussie 98 is your 91, then your 110 must be more than our 110..
     
  18. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    This is what I use when I race my car at the track. I mix it 50/50 with 93 pump fuel. Our fuel is rated at an average of the Research and Motor Octane ratings, so R+M/2. For this fuel, 114+106/2=110

    https://www.sunocoracefuels.com/fuel/standard

    That is probably more than I need, but octane figures out to 101.5 for the mix. It is cheap insurance. Racing at the track is different than anything you do on the street. You are holding the engine at WOT at maximum loading for 11-14 seconds. If you have any detonation, it is unlikely you will hear it at WOT, and it will do damage to the engine.

    There is no way to launch a Buick with a healthy 455 using any kind of street radial. It will be a very frustrating experience as the tires will spin no matter what you try. Drag Radials are best IMO.

    If your 71 Stage1 has the original Q-jet, that will be 7041242, and that is an 800 CFM carburetor. The Q-jet isn't really a vacuum secondary carburetor. The secondaries are mechanical, but there are air valves up on top that open with engine demand if they are adjusted correctly for the engine.

    BTW, the switch should provide a direct connection when activated, so 0 ohms. Most good meters have a continuity checker with an audible tone for testing continuity. So you just put the meter across the switch and activate the switch and you hear the tone, the switch is good.
     
  19. OZGS455

    OZGS455 Oh what a wonderful day!

    Thanks Larry, you are a wealth of info mate,
    Ive tracked a pair of Chev rally steelies down 15x10 and Ill buy a pair of Mickey Thompson ET Streets, sticky Drag radials, theres also some MT slicks 26x15x8.5
    Et Streets which width you reckon for the 10" rims under my rear ?
    255, 265, 275, or more?
    My old 1971 XYGT Ford Ive ran down the strip over 200 times,
    Sold it to buy the GS,
    It ran a 4V Headed 351 Cleveland D-block , fully balanced, big hyd cam,
    4-1 tube headers and 750 double pumper Holley,
    Was 4 speed toploader Hurst shifted and running a 31 spline tru track 9" Ford rear .
    I built her up from a wreck over 4 yrs and driven 29,000 hard miles kn the last 8 years, lotsa blood sweat n tears in that car , ran best 14.1@100.6 and could run 14.4 all day.
    Hard to be consistent with 4 speed and a 3.25 rear though.
    Car covered all the bases, street, drags, circuits, long trips.
    Bit sad to see her go but the 455 Buick GS has softened the blow
     

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  20. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    I like it Oz, and a 4 door to boot. Probably surprised a few motorists with that one, but the color doesn't really blend you in to traffic.:D

    10" rims need 5 1/2" to 5 5/8" back spacing to fit in the stock wheel wells. That's about the limit. You'd be safer with an 8" wide rim and 4 1/2" backspacing. That is what I run with 275/60R-15 MT's.
     

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