Hours vs. Miles? | FerrariChat

Hours vs. Miles?

Discussion in 'Technical Q&A' started by PT 328, Sep 7, 2009.

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  1. PT 328

    PT 328 F1 Rookie
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    May 1, 2005
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    This is something that I have thought about for quite some time.

    How come a cars usage is logged in miles and not in hours like boats? If one sits in traffic there would be less miles but more hours put on the engine. Not an ideal manner in which to identify use.
     
  2. Jedi

    Jedi Moderator
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    Often thought the same thing. No makeadasense
     
  3. eulk328

    eulk328 F1 Rookie

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    I suppose you also want to account for clutch, gearbox, diff., wheel bearing, brake wear etc. at the same time. Granted on a boat you have some other wear points too like rudder controls etc. but not to the same extent as in a car. Sitting in traffic is probably pretty insignificant from an engine wear standpoint especially with modern fuel injected cars (versus less accurate fuel mixture of carb'ed cars).


     
  4. donv

    donv Two Time F1 World Champ
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    I think race cars usually are measured in hours.
     
  5. AceMaster

    AceMaster Three Time F1 World Champ

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    #5 AceMaster, Sep 7, 2009
    Last edited: Sep 7, 2009
    Then you would have "hour roll-backs" instead of odometer rollbacks.

    Also, if it was in hours instead of miles, then cars that are driven on the highwway more often will have higher mileage with lesser time since you would be racking up the mileage iess time than city driving. For example, 60 miles per hour on the highway for 2 hours would give you 120 miles, but how many hours of city driving would it take you to run up 120 miles?
     
  6. Paul_308

    Paul_308 Formula 3

    Mar 12, 2004
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    Why not TOTAL REVOLUTIONS on the engine? Measured in MegaTurns

    or TOTAL REVOLUTIONS on the wheels? Measured in KiloTurns

    or TOTAL REVOLUTIONS on the government? Measured in shots fired/revolution
     
  7. Aedo

    Aedo F1 Rookie

    Feb 22, 2006
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    I suspect the reason started off for simplicity and clarity to non-technical owners.

    BMWs have used a combination hr/mileage system for about 20yrs. There is an indicator on the dash which counts down to a service based on useage patterns, mileage and time as opposed to simply mileage.
     
  8. Island Time

    Island Time F1 World Champ
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    It would also cut down on pollution and gas comsumption. Cars would idle alot less. They'd cut their engines off at red lights. ;)
     
  9. irondogmike

    irondogmike F1 Rookie

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    #9 irondogmike, Sep 8, 2009
    Last edited: Sep 8, 2009
    I love it..lol
    at every construction site you'll find machinery left on with no one in it during breaks or lunch. Because the equipment is charged in cost by how much its used in hours
     
  10. Mitch Alsup

    Mitch Alsup F1 Veteran

    Nov 4, 2003
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    Note: This second one is directly related to miles.

    ON the first one: Does a revolution at 1000 RPMs and low throttle position equal a single revolution at redline and wide open throttle?

    {You can measure airplanes in hours because the engine is producing 70%-ish of its rated HP all the time in the air.}
     
  11. Tom_C

    Tom_C Karting

    Feb 20, 2008
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    #11 Tom_C, Sep 8, 2009
    Last edited: Sep 8, 2009
    usually it's the opposite, as large companies like a few I've worked for charge their divisions rent based on the hours on the equipment, and when I was a PM I'd chew your ass for leaving the equipment running during breaks or lunch... now if it was a T and M job, and the inspectors were checking the meters.... ;)

    Whats really fun is that the old Cat dozers (probably more, but I know them for sure) had your typical hour meter, but it didn't keep accurate time, and sped up and slowed down with the revolutions of the motor. Old Superintendant told me one time that he had a job where they paid based off the equipment hours. After the first week of running it at fairly low rpms, and getting shafted on his paycheck, he figured it out. Unless he was on break, he kept it wide open, and made much better money..... :)
     
  12. bill brooks

    bill brooks F1 Veteran
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    cause hobbs was a brit, not an italian.
     
  13. PT 328

    PT 328 F1 Rookie
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    Some interesting thoughts. I think ideally both hours and miles should be used.
     
  14. Mike Florio

    Mike Florio Formula Junior

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    #14 Mike Florio, Sep 9, 2009
    Last edited by a moderator: Sep 7, 2017
    I've had a Hobbs meter on my 308/GT4 for years. It's mounted right next to the coils and picks up 12V off the B+ post on the coil. I suppose you could pick up the D post (wire to the distributor) maybe inductively, and count the pulses or build a little circuit with a D to A converter controlling the voltage to to the Hobbs meter - more pulses per second=higher voltage to Hobbs=faster count.

    Whenever I change the oil filter I mark the Date, Mileage and Hobbs reading on the bottom of the filter with a magic marker.
    Image Unavailable, Please Login
     
  15. kaamacat

    kaamacat Formula 3

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    My thought on that is the usage TYPE........ Most hour meters on, lets say commercial equipment, mowers, tractors are at WOT as designed to be. Boats are similar, running at 3000+ rpms (and remember these are 5500-5700 max rpm machines) and the sheer load they are handling is far above any car.
     
  16. miketuason

    miketuason F1 World Champ
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    Not sure about this but, aren't F1 also logged in hours?
     

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