View Poll Results: How should I overdrive my MPII blower???

Voters
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  • 10% OD supercharger pulley + stock jackshaft

    4 26.67%
  • 7-10% OD supercharger pulley + stock jackshaft

    1 6.67%
  • 94/95 SC pulley + 10% jackshaft

    7 46.67%
  • 94/95 SC pulley + 5% jackshaft

    3 20.00%
Results 1 to 13 of 13

Thread: How should I OD my MPII?

  1. #1
    Join Date
    Jun 2002
    Location
    Shorewood, IL
    Posts
    1,592

    How should I OD my MPII?

    I have a couple options here and I want opinions on the best way to OD the SC. It already has the 10% sc pulley, but I know it's a better option to run the jackshaft OD pulley to keep belt slip at a minimum. Engine is stock with 86k miles. It's a junkyard 95 motor with new bearings and seals.

    I have the MP springs, catless exhaust, K&N intake mod, underdrives, stock 36's for now with stock 94/95 plenum, MP FMIC. Any info is appreciated. Car will obviously need injectors and the inlet plenum. That's next on the list.
    Last edited by tydlwavs; 01-14-2009 at 04:17 PM.

  2. #2
    Join Date
    May 2004
    Location
    Va. Beach,Va.
    Posts
    6,317
    Depends on how much od you want. For 10% od I say the best with the least slip is a 10% crank pulley.
    SCCOA Member #2406
    '94 SC AUTO - $$$$ Pit
    http://www.sccoa.com/forums/garage_v..._vehicle&id=19

  3. #3
    Join Date
    Jun 2002
    Location
    Shorewood, IL
    Posts
    1,592
    I have underdrives.

  4. #4
    Join Date
    Jun 2003
    Location
    Kentucky
    Posts
    1,435
    Pitch the underdrives and run the OD Crank and Jackshaft with a stock supercharger pulley. I didnt see much help at all from the underdrives and with trying to keep belt slip at a minimum you want to have as much contact as possible on the SC pulley. Just my two cents.
    Anthony Arnold
    Home of "No Cash Racing!"

    Silver 90 AOD 12.03 Shootout 2010

    Black 92 AOD 12.77@109.5 10/12/07

  5. #5
    Join Date
    Nov 2004
    Location
    Brantford, ON
    Posts
    5,370
    Personally, 5% SC and 5% jackshaft.

    Fraser

  6. #6
    Join Date
    Jun 2002
    Location
    Blair, Nebraska
    Posts
    3,200
    Quote Originally Posted by fturner View Post
    Personally, 5% SC and 5% jackshaft.

    Fraser
    That's what I did. On the dyno, I was starting to have a bit of belt slip towards the end, but I think if I had the MP springs - I wouldn't have had the slip.

    -Melon

  7. #7
    Join Date
    Jul 2003
    Location
    Ottawa, Ohio
    Posts
    5,186
    Run 15%, 5 on the SC and 10 on the JS, and keep the UD's. I ran the MP 10 rib 15% kit on mine and made 265rwhp on a stock block.
    SCCoA Member#: 2515
    1990 SC AOD 2.1L Kenne Bell
    11.676 @ 121.35 mph

    My Garage

  8. #8
    Join Date
    Jun 2002
    Location
    Shorewood, IL
    Posts
    1,592
    I'd like to stick with 5-10% OD on the blower.

    -Todd

  9. #9
    Join Date
    Apr 2002
    Location
    St. Charles, MO
    Posts
    19,789
    Overdriving with the crank pully and jackshaft is best, because it increases the surface area for the supercharger belts to grip.

    David
    91 SC AOD 4.2..2.3 Whipple........10.92 @ 126.70
    93 SC AOD 347 Turbo.................10.04 @ 138.99
    My Garage

  10. #10
    Join Date
    Jun 2002
    Location
    Shorewood, IL
    Posts
    1,592
    I was told that the 10% SCI jackshaft overdrives the crank 5% and the blower 5%. Is that true? Just want to verify this.

  11. #11
    Join Date
    Apr 2002
    Location
    St. Charles, MO
    Posts
    19,789
    Quote Originally Posted by tydlwavs View Post
    I was told that the 10% SCI jackshaft overdrives the crank 5% and the blower 5%. Is that true? Just want to verify this.
    Todd,

    The overdrive on my ESM 10% jackshaft pulley is all on the supercharger belt side (it's 10% larger OD). The portion that is driven from the crankshaft pulley is the same diameter as stock and still uses a stock belt.

    Don't know anything about how SCI does it.

    David
    91 SC AOD 4.2..2.3 Whipple........10.92 @ 126.70
    93 SC AOD 347 Turbo.................10.04 @ 138.99
    My Garage

  12. #12
    Join Date
    Jun 2002
    Location
    Shorewood, IL
    Posts
    1,592
    I can't get to the search function for some reason. I'll have to ask Ryan. I do have MP springs and I'm lookin pretty hard at the 94/95 pulley and a 10% jackshaft pulley so I am not quite running a full 10% OD. I'll see if my 5% belt fits this set-up.

    Just waiting on payment for my 5% and the 10% sc pulley to make my purchase later today.

  13. #13
    Join Date
    Sep 2002
    Location
    Outside of Chicago
    Posts
    1,075
    Quote Originally Posted by fturner View Post
    Personally, 5% SC and 5% jackshaft.

    Fraser
    I got the same thing goin on. No complaints.

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