Page 1 of 4 123 ... LastLast
Results 1 to 10 of 38

Thread: 7 1/4" triple disk clutch

  1. #1

    Default 7 1/4" triple disk clutch

    Thanks to Andygtt from pistonheads for helping me get this part of the project moving in the right direction, and Dave from Jetstream for sorting the flywheel. I wish there were more DIY guys on this side of the pond.

    It looks like this Powertrain Technology 7 1/4" triple disk clutch is going to fit without causing any grief. It is rated for 900 ft-lbs (300 per disk), is very, very light, and will (I hope!) be as easy to slip and modulate as the factory clutch. The custom steel flywheel is also much lighter than stock. I'll post comparative weights in a few days.

    Because the assembly is so much lighter, and because the weight is located closer to the axis of rotation, this thing is going to have a much smaller moment of inertia than the factory setup. This will deliver more power to the tires because it isn't being wasted accelerating a large rotating mass.

    I know free rev'ing is a bit juvenile, but I'm looking forward to blipping the throttle with light crank pulley and light clutch/flywheel. I've always enjoyed how race engines gain and lose revs so quickly.

    The Powertrain Tech release bearing is taking some work to adapt to our slave cylinder, but I have a top of the hill fabricator on the job and expect the end result to be quite sturdy.



    Jeff
    Last edited by NobleM400; 04-27-2012 at 08:18 PM. Reason: corrected power rating

  2. #2

    Default

    Looks great! whats the price on that setup?
    "Some people play hard to get... I play hard to want."
    Noble: 05 M12, M400 turbos, RPI water/oil cooling, RPI Exhaust

  3. #3
    Join Date
    Jul 2010
    Location
    Portland, Oregon
    Posts
    375
    Rep Power
    8

    Default

    Beautiful, nicely finished Jeff. Hope you'll share a sound track of some fast engine blips when you get it running.
    2007 M400, NUS 206

  4. #4
    Join Date
    Aug 2011
    Location
    SoCal
    Posts
    402
    Rep Power
    7

    Default

    Very nice. Please let us know how it works and keep drawings for the release bearing mod.

  5. #5
    Join Date
    Jan 2009
    Posts
    270
    Rep Power
    10

    Default

    Your using a different release bearing to me... interested to see yours as if its better than mine I will swop so keep me posted

    my car lost under 50bhp from flywheel to wheels with this setup and it was much lighter than std and easy to modulate... be warned if you ride the clutch you will kill it (as with many multiplate systems).

    the cost is comparable to an upgrade stock clutch and fitenza flywheel and noble bearing (as these all need replacing).... Jetstream do the flywheel and you can buy your clutch and bearing direct but otherwise its a direct swop

    To be fair I spent nothing on development of this clutch as the first attempt worked

    If only this was true for everything on the car lol

  6. #6
    Join Date
    Jan 2009
    Posts
    270
    Rep Power
    10

    Default

    for reference I lightened my flywheel a further 1kg over your one by machining outside the clutch face...

    9kgs Stock flywheel
    7.5kgs lightened stock flywheel
    3.8kgs Fitanza alloy flywheel
    4.8kgs Jetstream flywheel for tripple plate clutch
    3.8kgs Jetstream lightened flywheel

    7.5kgs Stock clutch
    4.8kgs tripple plate clutch

    so stock setup weighs 16.5ks... above setup weighs 9.6kgs with the potential to lighten to 8.6kgs.... so saving of nearly 8kgs, add in the near 2kgs saving on the pulley and you loose nearly 10kgs from engine rotational masses.

    I have a goal to loose yet another 50kgs from the car so im looking for other places to save this kind of weight lol

  7. #7
    Join Date
    Mar 2010
    Location
    Las Vegas
    Posts
    789
    Rep Power
    10

    Default

    Sweet setup!!!
    2010 Rossion Q1 Turbohoses
    2014 Úlan DP02
    2012 McLaren MP4-12C
    2013 Radical SR3 RS
    1999 Mazda Spec Miata
    1957 Corvette Fuelie Vintage Road Racer

  8. #8
    Join Date
    Jul 2010
    Location
    Portland, Oregon
    Posts
    375
    Rep Power
    8

    Default

    Quote Originally Posted by andygtt View Post
    .....my car lost under 50bhp from flywheel to wheels with this setup and it was much lighter than std and easy to modulate...
    Andy
    Good to know. To put your <50bhp loss into perspective, how much bhp would you estimate that your car lost between flywheel to wheels with the original flywheel and clutch.
    2007 M400, NUS 206

  9. #9
    Join Date
    Jan 2009
    Posts
    270
    Rep Power
    10

    Default

    60bhp may 70bhp max id say with the stock setup... I had super sticky 295 048s on at the time as well

  10. #10
    Join Date
    Aug 2011
    Location
    SoCal
    Posts
    402
    Rep Power
    7

    Default

    Smaller moment of inertia effects spool up time, not peak HP.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •