NZHondas.com Membership is Open | Becoming an Exclusive Member has a number of benefits, you get an NZHondas.com sticker, a credit card style membership card, all of your limits on the forum are increased
Results 1 to 12 of 12
  1. #1
    700rpm (Idle)
    Join Date
    Aug 2008
    Posts
    87
    Location
    Auckland

    Unorthodox Racing Ultra Sc Pulley

    Has anyone here replaced their stock pulley with a lighter pulley?

    There's all this talk that it's the best bang for buck improvement in HP and Torque gains... Several forums out there talking about the Accord Euro's and TSX's swear by it...

    Product examples:
    http://www.heeltoeauto.com/unorthodo...a-tsx-cl9.html

    http://www.heeltoeauto.com/xlr8-perf...s-ua6-ua7.html


    From all the stuff i've read I still don't believe into the marketing of it. How does a lighter rotating pulley improve HP and torque... where the purpose of the pulley is to connect several components outside the engine to run things via belt. Mechanically to me it doesn't have any effect on the drive train, transmission or the outputting speed of your engine...

    It might affect throttle response or easier acceleration giving the placebo effect of it producing more power/torque (equivalent to pressing the gas pedal faster/harder)? ...


    If anyone's had any experience or knowledge on the subject would be great.
    Last edited by Commando; 15th June 2012 at 02:44 PM.

  2. #2
    6,000rpm (Max Torque) lancew's Avatar
    Join Date
    Aug 2010
    Posts
    1,907
    Location
    Auckland

    Re: Unorthodox Racing Ultra Sc Pulley

    A lighter pulley lightens the rotating assembly of the motor. Because the rotating assembly is lighter it is easier for the motor to work therefore freeing up power. I know how it causes power gains but I don't really know how to explain it, I'm sure someone else will be able to explain better than me though

  3. #3
    700rpm (Idle)
    Join Date
    Aug 2008
    Posts
    87
    Location
    Auckland

    Re: Unorthodox Racing Ultra Sc Pulley

    This is as best and as simplest that i've found an explanation on it.

    Underdrive pulleys - Wikipedia, the free encyclopedia

    I guess the parasitic effect may well be true. Ie a similar issue occurs when an engine is super charged (not efficient).

    So this lighter pulley is technically increasing the efficiency of driving the accessories (even though it says under drive but the pulley is larger than stock).

  4. #4
    Support Team: Forum Admin Matty's Avatar
    Join Date
    Sep 2002
    Posts
    16,871
    Location
    Hastings

    Re: Unorthodox Racing Ultra Sc Pulley

    The "parasitic effect" is true, there's no ifs or buts about it - less effort = more power freed up.

    They're called underdrive pulleys because they turn the ancillaries like the water pump slower due to the larger pulley size. An overdrive pulley would turn the ancillary faster, that's why you fit a smaller snout pulley to overdrive a positive displacement supercharger.
    Bloody Volvo driver.

  5. #5
    3,000rpm (Grandma Drag) DA Skunk2's Avatar
    Join Date
    Sep 2007
    Posts
    234
    Location
    Auckland

    Re: Unorthodox Racing Ultra Sc Pulley

    Quote Originally Posted by Commando View Post
    (even though it says under drive but the pulley is larger than stock).
    I'm pretty sure an underdrive 'crank' pulley is smaller than stock not larger. (If its an underdrive 'accessory' pulley then it's larger)

    Quote Originally Posted by Commando View Post
    It might affect throttle response or easier acceleration giving the placebo effect of it producing more power/torque (equivalent to pressing the gas pedal faster/harder)? ...
    I'm no expert so this is just a guess but wouldn't the lighter pulley = less un-sprung weight/less effort to spin = less energy lost = more power?
    Also those pulleys are for alternator only so no power steering or A/C, already a power gain with not having to run those.

    [edit]Beaten to it by Matty [/edit]

    A lighter pulley matched with lightened flywheel surely would free up some power I would have thought no idea what hp wise, but even if its just improved throttle response that's still a gain and could be worth it to someone?
    CJCI finally bought a ROTA... barp barp barp

  6. #6
    8,000rpm (B Series Redline!) lotusboy's Avatar
    Join Date
    Apr 2006
    Posts
    5,929
    Location
    Howick

    Re: Unorthodox Racing Ultra Sc Pulley

    The caveat that comes with aftermarket pulleys is the potential for them to be unbalanced. This has been linked before to premature big end bearing failure, and even the pulleys working themselves lose and flying off (Paging the frozen snapper / aaron)

    Heeltoes gear is known to be good, but is it worth risking your motors long term health for a few extra hp?
    The internetz its serious business

  7. #7
    4,000rpm (Taxi Drag) PCTypeR's Avatar
    Join Date
    Jun 2010
    Posts
    742
    Location
    Christchurch

    Re: Unorthodox Racing Ultra Sc Pulley

    Quote Originally Posted by lotusboy View Post
    The caveat that comes with aftermarket pulleys is the potential for them to be unbalanced. This has been linked before to premature big end bearing failure, and even the pulleys working themselves lose and flying off (Paging the frozen snapper / aaron)

    Heeltoes gear is known to be good, but is it worth risking your motors long term health for a few extra hp?
    This is why I went from a lightweight pulley back to stock. Butt dyno noticed no difference.
    143wkw 1996 Integra Type R

  8. #8
    700rpm (Idle)
    Join Date
    Aug 2008
    Posts
    87
    Location
    Auckland

    Re: Unorthodox Racing Ultra Sc Pulley

    Thanks gents it's definitely put this into perspective and I think this is one component I wont bother with if it does have bad side effects.

  9. #9

    Re: Unorthodox Racing Ultra Sc Pulley

    Genuine Honda N1 crank pulley for the win.

  10. #10
    Banned 700rpm (Idle)
    Join Date
    May 2010
    Posts
    177
    Location
    Palmerston North

    Re: Unorthodox Racing Ultra Sc Pulley

    Quote Originally Posted by DS Racing View Post
    Genuine Honda N1 crank pulley for the win.
    where do you get these from man??

  11. #11
    8,000rpm (B Series Redline!) lotusboy's Avatar
    Join Date
    Apr 2006
    Posts
    5,929
    Location
    Howick

    Re: Unorthodox Racing Ultra Sc Pulley

    Quote Originally Posted by DS Racing View Post
    Genuine Honda N1 crank pulley for the win.
    Quote Originally Posted by B PORTN View Post
    where do you get these from man??
    The internetz its serious business

  12. #12
    Team NZH: Order of Merit Horny_Devil's Avatar
    Join Date
    Jun 2002
    Posts
    29,034
    Blog Entries
    1
    Location
    Auckland

    Re: Unorthodox Racing Ultra Sc Pulley

    Quote Originally Posted by DS Racing View Post
    Genuine Honda N1 crank pulley for the win.
    they do N1 pulleys for accord Euro's and TSX's?
    Quote Originally Posted by permaisuri View Post
    ooh yeah, i read it differently.... sorry, im asian with 4 eyes... shouldve read better....

Similar Threads

  1. Hi from Ultra Racing NZ
    By PRO Wholesale in forum New User Introductions
    Replies: 6
    Last Post: 20th November 2010, 01:06 PM
  2. Unorthodox Racing Parts
    By Dezigns in forum Competition
    Replies: 2
    Last Post: 1st November 2002, 07:13 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
NZHondas.com
Disclaimer: The New Zealand Honda Club is not affiliated with Honda New Zealand in any way.