Page 1 of 3 123 LastLast
Results 1 to 15 of 43

Thread: sn 2000

  1. #1
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20

    sn 2000

    i have a sn2000 blower on my 89 stang it was rebuild 2 years ago by paradise ??? i want to know if i can put another pully to get more power out of it can it take it ???? and or some other tricks thanks

  2. #2
    SCH Moderator "SN Guru" speedytang's Avatar
    Join Date
    Dec 2002
    Location
    Marengo, Ohio
    Posts
    2,028
    Either go with a 3.75" pulley on the Supercharger or get a 7" crank pulley. IT really depends on you combination but you will see about 7psi at 4500 rpm. Just don't over-rev it or you could damage the impeller short shaft that the balls rotate around. ASP has you pulleys and they around $59.

  3. #3
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20

    SN 2000

    [QUOTE=speedytang]Either go with a 3.75" pulley on the Supercharger or get a 7" crank pulley. IT really depends on you combination but you will see about 7psi at 4500 rpm. Just don't over-rev it or you could damage the impeller short shaft that the balls rotate around. ASP has you pulleys and they around $59.[/QUOwhat you mean dont overturn the blower whats that mean my car stops making power at 5600 rpm is that to high for the blower or ??? what boost will i get at 5700 rpm thanks.

  4. #4
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20

    sn 2000

    what you mean dont overturn the blower whats that mean my car stops making power at 5600 rpm is that to high for the blower or ??? what boost will i get at 5700 rpm thanks

  5. #5
    Junior SCH Member
    Join Date
    Nov 2003
    Location
    Bay Area, CA
    Posts
    9
    The SN series supercharger has a maximum impeller speed of around 40,000rpm. Anything over this maximum is overturning the blower and subjects the blower to increased heat and friction which causes wear. This will damage the blower and require a rebuild. If you run the stock 6" crank pulley and 4" blower pulley your supercharger will be spinning 39960rpm @ 6000rpm (engine rpm). If you go to a 3.75" blower pulley and keep the 6" crank pulley your impeller speed will increase to 42624rpm @ 6000 engine rpm. This will increase your boost but also increase the wear on internal parts of your supercharger. You can figure out the impeller speeds using the equation below.

    Crank Dia./Blower Dia. x RPM x Blower Ratio = Impeller Speed

    The blower ratio of SN series Paxton blowers is 4.44:1

  6. #6
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20
    can i put an oil cooler on it is there such a thing ,that way it will keep it cooler and make it last

  7. #7
    SCH Moderator "SN Guru" speedytang's Avatar
    Join Date
    Dec 2002
    Location
    Marengo, Ohio
    Posts
    2,028
    The SN2000 does fine at 45000 rpm but DO NOT miss to many shifts or you will over rev the unit. The cooler will help keep the temperature down for every day use and gives more boost because the cooler fluid allows the ball drive to get traction on the internals. Now what I am getting ready to tell you I am not recommending just telling you my setup. I run a VR4 which is the race ball drive. I have street driven and raced the unit for 6+ years and run a cooler. I race the car and shift at 6800rpm have a 3.75" and a 7" crank pulley. This supercharger I take apart and inspect every winter and at 40k miles on the supercharger just replaced the rear seal which was a new design from the SN2000. I replaced the Impeller shaft and Balls last year but they really showed no damage but went ahead and got the parts from Paradise just in case they went belly-up. I have a 3.5" pulley ran it once and seen 15psi but for the street I didn't need it since I can build 12psi at 5800 rpm with the 3.75" and on the street I usually shift no higher than 5500rpm anyways. The reason I am giving warning is not really the rpm but it is a factor, but that I have a Billet Impeller and it can handle the 60k+ rpm without destroying itself and sending parts into the intake manifold.

  8. #8
    SCH Member
    Join Date
    Jan 2004
    Posts
    54
    Quote Originally Posted by PropheZ

    Crank Dia./Blower Dia. x RPM x Blower Ratio = Impeller Speed

    The blower ratio of SN series Paxton blowers is 4.44:1
    This was actually what i was looking for right now! Thanks!

  9. #9
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20
    hmmm k my car with my setup on the dyno my car makes power up to 5600 rpm and i have my rev limiter set to 5600 rpm so i cant really over rev the blower i think lol so what basically should i just change the pully??? maybe you can give me more details now that you know i can only rev up to 5600 rpm thanks.

  10. #10
    SCH Moderator "SN Guru" speedytang's Avatar
    Join Date
    Dec 2002
    Location
    Marengo, Ohio
    Posts
    2,028
    You can still over rev the blower. Just because you shut off spark or fuel does not mean your engine or blower will not do a rpm spike. Example. Set your rev limiter at 3000 rpm then hold the throttle open at that setting and put the clutch in or put the car in 'N' and you will see your tach rev and probably go past 7k rpm. Without knowing your engine setup you could probably be out of steam at 5200 rpm anyways and just be pushing throttle for no real increase. Nothing is as simple as it seems. Give some car background and maybe I can give you my personal opinion if it is worth going over 6psi or not.

  11. #11
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20
    backround as what you mean . what i have done to the engine

  12. #12
    SCH Moderator "SN Guru" speedytang's Avatar
    Join Date
    Dec 2002
    Location
    Marengo, Ohio
    Posts
    2,028
    Give some engine information

  13. #13
    Junior SCH Member
    Join Date
    Sep 2003
    Posts
    20
    i got full exhaust with long tubes no cats b303 cam explorer upper lower 70ml throttle body 255 fuel pump just msd ignition no btm and set at 5600 rpm thats about it and as well the sn2000 with at 6 pounds of boost also if i want 9 pounds of boost what do i need and is that going to much thanks

  14. #14
    SCH Moderator "SN Guru" speedytang's Avatar
    Join Date
    Dec 2002
    Location
    Marengo, Ohio
    Posts
    2,028
    Change the FMU disc, Put plugs at .032-.035. Change to a 3.75" pulley and you might see 8psi and to bad you have the 'B-303' cam because it is costing you power and the stock cam would be much better. You really need some type of BTM. Set timing to 14 degrees and have the BTM pull back 1 degree for every 1psi of boost. Have you ran it at the track yet to give timeslip numbers so can get a rough estimate of horsepower.

  15. #15
    SCH Member
    Join Date
    Feb 2004
    Posts
    52
    Quote Originally Posted by speedytang
    Change the FMU disc, Put plugs at .032-.035. Change to a 3.75" pulley and you might see 8psi and to bad you have the 'B-303' cam because it is costing you power and the stock cam would be much better. You really need some type of BTM. Set timing to 14 degrees and have the BTM pull back 1 degree for every 1psi of boost. Have you ran it at the track yet to give timeslip numbers so can get a rough estimate of horsepower.
    I have a simular set up on my car, I have a stock cam but was going to go to a B-303 But after hearing what you said Perhaps I wont, Why is the stock cam worth more power?What size disk in the fmu? Will the blower last with these mods? Thanks

Posting Permissions

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