Driveline vibration

Discussion in 'Technical' started by ZXOCET, Jun 10, 2016.

  1. ZXOCET

    ZXOCET Member

    I recently purchased a one-piece alloy, foam-filled tailshaft from the USA, manufactured by Inland Empire Driveline.

    As a precaution I took it to Sydney Driveline Service in Greenacre to confirm balance of this new unit, only to discover not properly balanced for high speed - these guys did a great job and very pleased with the result.

    Just wondering if anyone else has had vibration issues with new one-piece drivelines bought off-the-shelf?
     
  2. lovmyzed

    lovmyzed Member

    out of curiosity what do you call high speed?

     
  3. ZXOCET

    ZXOCET Member

    High speed on their balancing machine. The shaft had one balancing tag attached at one end but not the other. IMO $165 well spent
     
  4. tassuperkart

    tassuperkart Its a lie I tell you!

    Then the money on some fandangled funky tailshaft wasnt.
    E
     
  5. ZXOCET

    ZXOCET Member

    Just a lightweight one-piece alloy tailshaft, not carbon fiber
     
  6. East Coast Z

    East Coast Z Well-Known Member

    Questions......

    Did you order this tailshaft as a custom built item?
    I checked out the Inland Empire Driveline site & didn't notice any foam-filled tailshafts advertised.
    It appears these guys specialise in hot rod drivelines.
    Why didn't you order a tailshaft from Coz or Z1?
    Their tailshafts are poven to work.
    Why take the tailshaft to Sydney Driveline Service to confirm the balance?
    Was there a problem?

    A Z32 engine in stock standard trim is redlined at 7,000rpm.
    If you are in 4th gear at redline, at what rpm is the tailshaft rotating?

    At what rpm did Sydney Driveline Service balance the tailshaft.
    At what rpm does a tailshaft rotate for "high speed"?
     
  7. ZXOCET

    ZXOCET Member

    The Inland Empire heavy duty alloy tailshaft was ordered and supplied by Coz. Foam filling was an option to counteract resonant vibration. I have a friend who fitted a one-piece carbon fiber driveshaft (also supplied by Coz and Inland Empire built) that gave annoying vibration at only 130 kph highway speeds. Maybe just a one-off out-of-balance vibration experience however that was the reason I took the precaution of having my tailshaft balance checked. I did not ask Sydney Driveline Service what rpm they take their dynamic balancing to.
     
  8. East Coast Z

    East Coast Z Well-Known Member

    This is the description on ConceptZperformance.

    Actual Weight: 15lbs

    Inland Empire Aluminum Driveshafts are manufactured from custom drawn 6061-T6 D.O.M. aluminum tubes for consistent strength utilizing 6061-T6 aluminum forged weld yokes for strengthened grain structure.
    Internal stress induced by the machining process is reduced by working with the grain structure resulting in a more durable product.
    This reliability is enhanced by our "State of the art" welding processes.
    Our products have passed Spicer's grueling dynamic reverse torsion testing and have qualified us as an authorized aluminum shaft builder.

    Competition

    Accepted By NHRA for all Super Categories, Competition Eliminator, and including Pro Stock.
    Accepted by IHRA for competition in all categories.
    All NHRA Super Categories and fast including SFI "43.1" Certified shafts for Competition Eliminator and Pro-Stock.

    6061-T6 aluminum forged weld yokes for strengthened grain structure.
    Internal stress reduced by machine work done with the grain structure.
    Custom drawn 6061-T6 D.O.M. aluminum tube for consistent strength.
    State-of-the-art welding processes for improved reliability.

    Inland Empire Driveline Service's products have passed Spicer grueling dynamic reverse torsion fatigue testing requirement.

    One of the very few Spicer authorized aluminum drive shaft builders in the world.
    Inland Empire Driveline Service also routinely makes proof tests in static torsion.

    Note: ALL aluminum driveshafts will exhibit a metallic resonating noise that the original 2pc steel driveshaft naturally dampens.
    This is normal and will not affect performance, but if you are concerned about cabin noise, you may prefer a Steel Driveshaft, which still provides significant weight savings over the OEM driveshaft, but is going to run quieter than aluminum.
    Inland Empire now also offers a foam filling option for aluminum driveshafts, which significantly reduces noise and resonance without adding any noticeable weight.
    This is the best weight to enjoy buttery smooth operation while still getting the weight savings of an aluminum driveshaft
    .
    Please allow 3-5 days for shipping with this option.

    I can see where you are coming from in relation to the balancing concerns & it would appear you have paid for a quality product.

    Have you contacted Coz about the requirement for the tailshaft to be rebalanced?
     
  9. ZXOCET

    ZXOCET Member

    I haven't contacted Coz yet, still waiting for a shipment from him first
     
  10. tassuperkart

    tassuperkart Its a lie I tell you!

    Mate, all these funky composite and ally tailshafts are just basically a woftam at the end of the day.
    They promise much and deliver nothing for the money.
    The number of those very trick looking but unreliable carbon shafts that have come apart is ludicrous.
    Ally shafts are more or less a marketing exercise.

    Because tailshafts have no offset weights and are just a rotating tube, they are not balanced to an rpm, like say a V8 or V6 crankshaft which are "Percentage" balanced to run smoother at particular rpm ranges.
    They are just turned over and balanced in the same way wheels are balanced radially. At an rpm sufficient to cause maximum out of balance deflection which is easiest to measure and correct for.

    If a tailshaft is made with any care, it doesnt need any balancing at all. But in order to keep costs down, they are just plonked together with a MIG and a couple of weights zapped on to account for poor assembly.

    Why do i claim this? Good mates of mine run a boutique automotive custom performance workshop and they make custom tailshafts for people.
    They dont ever balance the shafts they make. The are assembled and trued in a lathe with dial guages at each end. If they dont run out, they dont need balancing nor have they had one come back for vibration issues.
    Ive personally watched several being made and marvelled at the simplicity and speed of the assembly which flies in the face of the actual cost to have one made!

    As far as im concerned, tailshafts made from funky and exotic materials are simply a marketing exercise designed to haul in the well heeled, but gullible punters.

    Make mine a steel shaft thank you and aill deal with the couple of kilos extra weight by using a single exhaust if i actually gave a shite!!

    E
     
  11. Fists

    Fists Well-Known Member

    Powertrain weight is very different to chassis weight, the significance of individual components in the drive train varies with diameter/moment of inertia and where they are relative to diffs and gears so I'm not sure about drive shafts but heavier wheels are very noticeable in the response and feel of a car.
     
  12. tassuperkart

    tassuperkart Its a lie I tell you!

    No dispute there at all.
    But were talking less than a couple of kilos tops over more or less the same diameter on a tailshaft that does not contribute to unsprung weight on the car.

    Theres isnt a single person here on this forum, or just about any other forum who can state with any authority that the addition of a lighter (and in many cases) far less durable tailshaft would have ANY noticeable effect on any element of the cars performance.

    With bigger/heavier wheels and tyres, allowing for gyroscopic precession and so-on at high speed? The same.

    Not saying it doesnt happen at all. But, lets be realistic here. Even flat out, no-one here can say. "yep, my car definitely handles any differently because now run 19's in stead of 17's".

    Same for some funky-assed tailshaft....woftam. At what rate of acceleration would the inertia of a 3" tailshaft noticeably affect power to the wheels.....It wont.

    E
     
  13. AndyMac

    AndyMac Better than you

    I can.

    My aluminium tailshaft from a reputable source twisted under load with semi-slicks on during a z-national hill climb launch.

    It had a noticeable effect on performance.
     
  14. East Coast Z

    East Coast Z Well-Known Member

    My carbon fibre tailshaft made a noticeable effect on performance.
     
  15. Chrispy

    Chrispy Pretentious Upstart

    Lol! Would have felt like you were doing 200mph :p
     
  16. tassuperkart

    tassuperkart Its a lie I tell you!

    Hahahaha yer i bet it did!!!!!!!!!!!!! BANG!
    I probably should have stated a good/positive/increased horsepower noticeable on the ass dyno!!
     
  17. Fists

    Fists Well-Known Member

    I can definitely tell the difference between my 18x9.5"s and a set of dinky 16x6.5s, the weight difference is pretty clear when picking them up too. That's not even "I'm a really experienced driver so I can tell these things", I would say it's obvious. It's not so much top speeds and dyno figures that benefit but that feel of pick up the instant you get on the throttle. It's even more obvious when you're doing a sick skid and the vehicle mass plays a much smaller role in amplifying your compliment of genitalia.

    As for money, going one piece is pretty reasonable when the stock unis or carrier bearing go, and aluminium is a pretty modest up-sell over a steel unit. Assuming of course that they don't break and cause headaches.
     
  18. tassuperkart

    tassuperkart Its a lie I tell you!

    Well... duuude, thats hardly surprising wouldnt you think?
    in the scheme of things thats very much like comparing apples to oranges.

    Any noticeable "gains" from the "ass dyno" when changing tailshaft materials is mere placebo effect or delusions of granduer in more pronounced cases.
    Your brain is trying to justify the stupid costs of these funky tailshafts and makes you think your going better!!!!

    Id love to be bothered to actually mathematically work out the number of inch/Lbs of torque, soaked up by a tailshaft, a kilo or two weightier around its circumference in comparison to another tailshaft of steel when factoring the increase in tailshaft RPM as a car accellerates...Baaahahaha!!!!!!
    Yeeeeaaah, riiiight...... gotta be a fuylli shikk pile of hiding horsies right there.. Uleh!!!!!

    E
     
  19. rob260

    rob260 Administrator Staff Member

    For what it's worth when I had metropolitan direveshafts build the most recent shaft for the car (having experienced to c/f failures) they told me they balance at low speeds. It seems to work.
     
  20. ZXOCET

    ZXOCET Member

    Inland Empire website states that most driveshafts are balanced at 3,000 -> 3,500 rpm from the factory, however gear ratio changes and high-speed racing require the shaft to be balanced at 5,000 and up to 7,500 rpm
     

Share This Page