Results 1 to 6 of 6
  1. #1
    smacota1's Avatar
    Join Date
    Sep 2009
    Location
    South of Mason Dixon
    Posts
    1,162
    +1
    36

    '04 GPR1390GK Update

    Well........

    After dropping a valve on my KPG1390, and then having a EFI controller fail and wipe out two cylinders....I had a GK1390 laying around. Decided to drop it in and see how it ran.

    I have been playing around with a lot of different pump and prop setups and thought I would post them here for some feedback....

    My mods are as follows:
    GK1390 Fixed valves
    Riva Girdled Heads 91 Oct
    Stock Keyway (removed 3* key from the KPG)
    R&D Powershot (Thanks Water Woody)
    IR plate stage 4
    D plate modded
    1200 water box free flow
    Fernando Jetworx kit
    05 ho pump
    SS 800 Grate
    Cut R&D Tabs
    Sealed Shoe

    First prop I tried was a 6S8 boat prop..... 18/24 stock. Turned it 6700 @74.8 really sucked on bottom end especially with fixed valves

    Second prop was the custom setup I got from Tommy (2fast4u) 158MM Riva wear ring with 158MM DF setback, 13/22. Was able to turn it 7100 @ 77.1 Holeshot fair...but stab it a about 3500 and you better hang on.

    Yesterday put a modded boat prop 18/22 on and was able to see 7090 @ 75.3. Hole shot still sucked.

    I am waiting for my DF 13/23.5 to come back from Impros to try it out.( sucked up a rock and really messed a blade up) plus I am pretty sure I am a little rich on the top.

    Question????

    Should I put the 3* keyway back in? Does this performance appear to be what should be expected?

    The old setup used to perform better, but I never really got to test it out before the valve dropped. I seem to remember the KPG1390 turning around 7200 @ getting 78-79, but that was in not ideal water conditions...but I also had to mix about 20% Sunoco 108 due to higher compression.


  2. #2
    "just sayin".. jetdave56's Avatar
    Join Date
    Nov 2008
    Location
    JERSEY SHORE
    Posts
    4,495
    +1
    618
    I have a df 14/22 that the leading edge like you got chewed up...cavitate like mad but once on plane she goes...turned 7280 yesterday with the cooler air...why don't you like the 13/22 setback..you got some nice #s...might repitch to that...btw explain the "set back" advantages..is that something Impros can do to the DF...

  3. #3
    mtrager's Avatar
    Join Date
    Jul 2006
    Location
    Orlando, Florida, United States
    Posts
    2,443
    +1
    2
    Smacotal,

    I have a ported 1300 with keyway. It ran 78.9 yesterday with a 14/23 impros prop set back 50 thousands. I think the dyna flys are going to be a lot more fun to ride.

  4. #4
    smacota1's Avatar
    Join Date
    Sep 2009
    Location
    South of Mason Dixon
    Posts
    1,162
    +1
    36
    Quote Originally Posted by jetdave56 View Post
    I have a df 14/22 that the leading edge like you got chewed up...cavitate like mad but once on plane she goes...turned 7280 yesterday with the cooler air...why don't you like the 13/22 setback..you got some nice #s...might repitch to that...btw explain the "set back" advantages..is that something Impros can do to the DF...
    JetDave56,

    I do like the 13/22 158MM setup...just had a few different things and decided to try them all....I am sure Impros can do a setback. What I understand it helps eliminate cavitation, but there are more experts on here for this than I am. I am sure someone will post up more advantages.

  5. #5
    smacota1's Avatar
    Join Date
    Sep 2009
    Location
    South of Mason Dixon
    Posts
    1,162
    +1
    36
    Quote Originally Posted by mtrager View Post
    Smacotal,

    I have a ported 1300 with keyway. It ran 78.9 yesterday with a 14/23 impros prop set back 50 thousands. I think the dyna flys are going to be a lot more fun to ride.
    What RPMs did you turn? Is that a single pipe or triple? Yeah the DF's are really great....just had a few other things to try...

    I have two sets of HO pumps so now it makes it easier to do back to back when I get a chance....

  6. #6
    mtrager's Avatar
    Join Date
    Jul 2006
    Location
    Orlando, Florida, United States
    Posts
    2,443
    +1
    2
    Quote Originally Posted by smacota1 View Post
    What RPMs did you turn? Is that a single pipe or triple? Yeah the DF's are really great....just had a few other things to try...

    I have two sets of HO pumps so now it makes it easier to do back to back when I get a chance....
    That is my single pipe. Do not run a tach but rpms are above 7200. It looks like the 1390's like less rpm.

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. need a 04 knock sensor update
    By rapidacceleration in forum 4-Tec Performance
    Replies: 44
    Last Post: 04-04-2010, 06:57 PM
  2. wanted 04 piggyback update harness
    By jetskibill9999 in forum Sea Doo Classifieds
    Replies: 2
    Last Post: 09-01-2008, 10:53 PM
  3. How To: Install RR ECU after the knock sensor update 04 RXP
    By Green Hulk in forum Sea Doo How To & FAQs
    Replies: 15
    Last Post: 06-14-2008, 12:13 PM
  4. 04 knock sensor update.
    By 98Hawk in forum Sea Doo Open Discussion
    Replies: 1
    Last Post: 04-26-2007, 12:11 AM
  5. Help understanding the 04 knock sensor update.
    By Summitt in forum Sea Doo Open Discussion
    Replies: 17
    Last Post: 01-16-2007, 10:07 PM

Posting Permissions

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