Thread: Looking for information on why 2004 GTP's need a larger pulley

Results 1 to 9 of 9
  1. #1 Looking for information on why 2004 GTP's need a larger pulley 
    SE Level Member
    Join Date
    Dec 2018
    Location
    Lehigh Valley, PA
    Posts
    65
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    I've seen on multiple sites that sell pullies that they recommend adding .1-.2" to the pulley size with an 04 GTP compared to other cars, although the stock pulley size is the same at 3.8". Anyone know why that is? I'd really like to run a 3.4 inch pulley, and I don't think shelling our 100 bucks is worth it to only go down to a 3.6" pulley. I just ordered my headers, and Autolite 104's are a parts store trip away. I'll also be fabbing up my own fenderwell intake that I also plan on adding a "cold box" to. I'm designing an enclosure to run the intake tube through that can hold dry ice to really get intake temps down (for at least long enough to make a few passes before the dry ice vaporizes) I can get my hands on 93 octane here, and I usually run either 91 or 93 on a daily basis. Also, I'll be wrapping my headers to keep under hood temps down.

    Thoughts?
    Reply With Quote  
     

  2. #2 Re: Looking for information on why 2004 GTP's need a larger pulley 
    Killa Bee Scottydoggs's Avatar
    Join Date
    Aug 2010
    Location
    new jersey
    Posts
    39,919
    Thanks (Received)
    63
    Likes (Received)
    166
    Dislikes (Received)
    5
    got e85? if so get larger injectors and a tune and drop to a 3.2 pulley.

    or add a fcic and drop to a 3.2 on 93 octane, then if you want more add a meth kit, and a 2.8, you'll need a tuner in hand for meth.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
    Reply With Quote  
     

  3. #3 Re: Looking for information on why 2004 GTP's need a larger pulley 
    SE Level Member
    Join Date
    Dec 2018
    Location
    Lehigh Valley, PA
    Posts
    65
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    I'm staying mild with this car. Just want to know what I can get away with on pulley size with just what I listed. My fast car is a turbo LS C3 Corvette.
    Reply With Quote  
     

  4. #4 Re: Looking for information on why 2004 GTP's need a larger pulley 
    SE Level Member
    Join Date
    Dec 2018
    Location
    Lehigh Valley, PA
    Posts
    65
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    Oh, and E85 is very much a PITA to get here. There's only 3 stations that are kind of local, and one sells it in 5 gallon cans, leaving only 2 that actually have it at the pump, and those 2 are out of my way. Not really what I want to get into with my DD
    Reply With Quote  
     

  5. #5 Re: Looking for information on why 2004 GTP's need a larger pulley 
    Killa Bee Scottydoggs's Avatar
    Join Date
    Aug 2010
    Location
    new jersey
    Posts
    39,919
    Thanks (Received)
    63
    Likes (Received)
    166
    Dislikes (Received)
    5
    in the end the gen 5 is a tad better than a gen 3. why they end up just dropping to a 3.6 and not a 3.4 gains would be about the same cause the gen 5 is a better blower.

    98 Buick Regal GS, F body brakes, Caddy STS wheels, tinted tails L36 bottom end, lightly ported heads, 1.95 roller rockers, headers, gen 5 N* 3.0 pulley, FSIC, 42 lb injectors, a BrandonHall rebuilt trans, DHP tuned and AEM water/Meth injection https://goo.gl/gpV5kW
    Reply With Quote  
     

  6. #6 Re: Looking for information on why 2004 GTP's need a larger pulley 
    GrandPrix Junkie SgtMarshal's Avatar
    Join Date
    Feb 2012
    Location
    Kemmerer, Wyoming
    Posts
    4,701
    Thanks (Received)
    10
    Likes (Received)
    25
    Dislikes (Received)
    0
    the rules are different with a gen 5. you could run a 3.4 on your gen 5 if you installed a cam or an intercooler, otherwise stick to a 3.6.
    Reply With Quote  
     

  7. #7 Re: Looking for information on why 2004 GTP's need a larger pulley 
    Turbo is the way to go. Fivefingerdeathpunch's Avatar
    Join Date
    Sep 2009
    Location
    Rogers, MN
    Posts
    21,022
    Thanks (Received)
    21
    Likes (Received)
    45
    Dislikes (Received)
    0
    Factory power output is also higher on a 2004 compared to say a 2000 car because the blower is a better design. It makes more boost with a smaller pulley diameter drop than a GEN 3 supercharger.

    SMGPFC Member #1
    Reply With Quote  
     

  8. #8 Re: Looking for information on why 2004 GTP's need a larger pulley 
    SE Level Member
    Join Date
    Dec 2018
    Location
    Lehigh Valley, PA
    Posts
    65
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    Maybe I'll look into doing 1.9 ratio rockers and good springs when the weather warms up. I gotta do the headers as soon as they arrive though, cause I got a real nasty exhaust leak at the moment!
    Reply With Quote  
     

  9. #9 Re: Looking for information on why 2004 GTP's need a larger pulley 
    SE Level Member
    Join Date
    Dec 2018
    Location
    Lehigh Valley, PA
    Posts
    65
    Thanks (Received)
    0
    Likes (Received)
    1
    Dislikes (Received)
    0
    Headers should be here by Thursday. Hopefully I'll be able to find a warm garage to borrow to get them on. I found a great deal on a 3.4" pulley, but I'll wait to put it on until I have the other stuff it takes. I'm thinking of just going with meth injection right off the bat. I don't need this thing getting into kr.
    Reply With Quote  
     

Similar Threads

  1. 2004 GTP information center keeps resetting
    By mok4200 in forum General Tech Discussion
    Replies: 3
    Last Post: 11-23-2015, 10:19 PM
  2. 2004 -08 Grand Prix Information display help needed
    By Hammsman44 in forum General Grand Prix Discussion
    Replies: 2
    Last Post: 01-14-2013, 08:41 PM
  3. Larger Cam With Larger Rocker Ratio's?
    By pontiackid in forum 3.8L V6 Supercharged (L67)(L32)
    Replies: 19
    Last Post: 12-20-2009, 02:29 PM
  4. Larger pulley in Winter?
    By TheOtherNick in forum 3.8L V6 Supercharged (L67)(L32)
    Replies: 15
    Last Post: 11-03-2008, 02:38 PM
  5. GM part number for a 5 button Driver Information Center 2004 GTP
    By mnl119 in forum General Tech Discussion
    Replies: 0
    Last Post: 06-15-2008, 09:54 PM
Tags for this Thread

View Tag Cloud

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