3.2 swap Am I setup right?????

Discussion in 'Gen 1 & 2 - Engine, Exhaust, Drive Line & AC syste' started by Anonymous, Nov 22, 2019.

  1. Anonymous

    Anonymous SHO Member

    Joined:
    Apr 10, 2010
    Messages:
    273
    Likes Received:
    12
    Location:
    Philadelphia,PA
    Ok so I’m doing a 3.2 swap on my 93 MTX , I found a nice 3.2 with only 80k and decided to Proceed with just doing a swap. I’ve done some research on what was needed to complete this and saw that you need to switch all the 3.0 2 belt drive accessories over to the 3.2 , Ok cool! , so right now I’m setup with a 3.2 top and bottom end with a 3.0 MTX underdrive pulley ( cause I’m using the 3.0 2 belt setup ) but I went back and saw someone posted on a SHO group on Facebook about using the 3.0 top end on a 3.2 block and majority of everybody agreeing that using the 3.0 top end is the way to go cause they say the 3.0 cams are better , so is my setup with the whole 3.2 top and bottom with a MTX underdrive pulley gonna be a problem or do I really need to swap over the 3.0 heads ??? I want to make sure I’m not setup for any issues cause I thought you just take the whole 3.2 and just swap over the 3.0 belt drive
     
  2. sperold

    sperold Last to Know Supporting Member

    Joined:
    Aug 25, 2008
    Messages:
    3,516
    Likes Received:
    1,250
    Gender:
    Male
    Occupation:
    Mech. Tech.
    Location:
    Ontario Canada
    Here is some information:

    http://www.wikisho.com/wiki/Engine_Swaps?

    I have heard crank related stories about under-drive crank pulleys (as apposed to larger pullys on the accessories), so you should research that.

    The 3.0 cam stories are interesting, but I personally would leave the 3.2 intact.
     
    Last edited: Nov 22, 2019
    blk\blk90 likes this.
  3. Irish Pride

    Irish Pride Irish Inside Staff Member Super Moderators

    Joined:
    Dec 23, 2007
    Messages:
    2,244
    Likes Received:
    3,061
    Occupation:
    Owner of A Little Bit Of This And A Little Bit Of
    Location:
    MusicCityUSA
    The 3.2 has a larger displacement but less aggressive cams. The 3.0 cams installed in a 3.2 gives you the best of both. You can run it exactly like you have it no problem but you might plan to do the 3.0 cam swap in the future for better performance.

    -Chad
     
  4. rubydist

    rubydist SHO Master Staff Member Super Moderators

    Joined:
    Jun 25, 2007
    Messages:
    6,926
    Likes Received:
    2,800
    Location:
    Denver
    I have done it both ways, and imho for a daily driver the 3.2 cams are better. You will have more low end torque and get better gas mileage. The trade-off is above 5000 rpm you will have a little less power.
     
  5. Anonymous

    Anonymous SHO Member

    Joined:
    Apr 10, 2010
    Messages:
    273
    Likes Received:
    12
    Location:
    Philadelphia,PA
    So I’m a pretty much break even power wise ? Or won’t feel the difference with running 3.2 cams? Cause I’m also going to run a 3.0 MTX under drive pulley with the 3.2
     
  6. Anonymous

    Anonymous SHO Member

    Joined:
    Apr 10, 2010
    Messages:
    273
    Likes Received:
    12
    Location:
    Philadelphia,PA
    Well I would like to see somewhat of a difference in performance being that I’m going with a bigger displacement, I’m also going to run a MTX underdrive pulley with it as well
     
  7. Anonymous

    Anonymous SHO Member

    Joined:
    Apr 10, 2010
    Messages:
    273
    Likes Received:
    12
    Location:
    Philadelphia,PA
    Ok so once I get over 5k will I noticed the decrease in power ? Cause I’m also going to run a MTX under drive pulley with the 3.0 accessories on the 3.2
     
  8. Irish Pride

    Irish Pride Irish Inside Staff Member Super Moderators

    Joined:
    Dec 23, 2007
    Messages:
    2,244
    Likes Received:
    3,061
    Occupation:
    Owner of A Little Bit Of This And A Little Bit Of
    Location:
    MusicCityUSA
    Are you planning to use a MTX underdrive pulley?
     
    blk\blk90 and SHOMON like this.
  9. Irish Pride

    Irish Pride Irish Inside Staff Member Super Moderators

    Joined:
    Dec 23, 2007
    Messages:
    2,244
    Likes Received:
    3,061
    Occupation:
    Owner of A Little Bit Of This And A Little Bit Of
    Location:
    MusicCityUSA
    Run it like it is. If you think it's running a little flat in the upper rpms then plan on a Cam swap down the line.
     
  10. Anonymous

    Anonymous SHO Member

    Joined:
    Apr 10, 2010
    Messages:
    273
    Likes Received:
    12
    Location:
    Philadelphia,PA
    Yes
     
  11. rubydist

    rubydist SHO Master Staff Member Super Moderators

    Joined:
    Jun 25, 2007
    Messages:
    6,926
    Likes Received:
    2,800
    Location:
    Denver
    You will notice a lot more torque at engine speeds below 4000 rpm because of the combination of cam grind and additional displacement. Above 4-5k, it will be close to the same as your 3.0 was, except it drops off above 6k due to the cam grind.
     
  12. Anonymous

    Anonymous SHO Member

    Joined:
    Apr 10, 2010
    Messages:
    273
    Likes Received:
    12
    Location:
    Philadelphia,PA
    I thought the under drive pulley allows higher revs?
     
  13. luigisho

    luigisho SHO Member

    Joined:
    Nov 2, 2001
    Messages:
    8,903
    Likes Received:
    1,868
    Location:
    va beach,va
    Home Page:
    Not really going to help if the cam profile and heads can't breathe at the top. It's about valve timing and moving air.
     
    SHOMON likes this.
  14. Irish Pride

    Irish Pride Irish Inside Staff Member Super Moderators

    Joined:
    Dec 23, 2007
    Messages:
    2,244
    Likes Received:
    3,061
    Occupation:
    Owner of A Little Bit Of This And A Little Bit Of
    Location:
    MusicCityUSA
    The underdrive pulley doesn't allow for higher revs. The engine will still rev as high as it would before. With 3.2 cams you will lose power in the very upper rpms compared to 3.0 cams.

    The underdrive pulley reduces the weight of the rotating assembly and slows the rate at which the accessories spin. You will notice better throttle response with the underdrive pulley and your accessories will like you more after taking the car to 7K over and over.
     
  15. rubydist

    rubydist SHO Master Staff Member Super Moderators

    Joined:
    Jun 25, 2007
    Messages:
    6,926
    Likes Received:
    2,800
    Location:
    Denver
    Its sort of a semantics thing... The underdrive pulleys allow higher revs before you blow up the alternator from over-revving the alternator. But it doesn't do anything for the engine itself as far as revs, as Chad posted above.
     

Share This Page

If you wish to help keep SHOforum running, please click the donation button below