Jet Boat top speed
+ Reply to Thread
Page 1 of 3 1 2 3 LastLast
Results 1 to 14 of 29

Thread:
Jet Boat top speed

  1. #1
    Senior Master Technician
    Join Date
    Jun 2011
    Posts
    23

    Default Jet Boat top speed

    Hows it goin, I recently rebuilt a 78 tahiti super tiger and installed a big block chevy I built for it, estimated around 500hp. I rebuilt the jet drive with an a impeller loader scoop with a place diverter and red insert cone. So far ive held it wide open for about 6 to 7 seconds and hit 63 MPH on a gps. I can spin the impeller to 5200 rpm constantly so my HP estimate is about right. The question is from your experience, how long should it take me, holding it wide open, to hit the max speed, and what should I be seeing for a max speed with this type of hull. Thanks.

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    Senior Member
    Join Date
    Sep 2012
    Posts
    264

    Default

    Your there.

  4. #3
    Senior Master Technician
    Join Date
    Jun 2011
    Posts
    23

    Default

    Damn I was hoping for around 65-70 MPH, I wonder if I put a droop snoot, shoe and rideplate if i can lift her fat ass out of the water. Before we rebuilt it she would run about 60 but take forever to get there. Now the acceleration is stupid compared to before. Funny how I only gained 3 MPH

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member GT Jets's Avatar
    Join Date
    Jun 2008
    Location
    Morgan Hill
    Posts
    2,234

    Default

    Quote Originally Posted by Bobbylisa View Post
    Your there.
    GT


    Quote Originally Posted by Quickjet View Post
    Put a 300 on the back of it, Flywheel it and a nosecone. $15,000 later you'll have a 65 mph pile of shit......

  7. #5
    Senior Master Technician
    Join Date
    Jun 2011
    Posts
    23

    Default

    Funny, only trying to do the best with the hull I got man

  8. #6
    LP-25.com Infomaniac's Avatar
    Join Date
    Dec 2007
    Location
    New Port Richey, FL
    Posts
    16,855

    Default

    MPH is not generally the target with a jet. Being quick is their best attribute.
    If For Some Reason I Do Something Worthy Of Recognition. God Provided The Ability And Deserves The Credit.


    QE 439 Twin Turbo

  9. #7
    Senior Master Technician
    Join Date
    Jun 2011
    Posts
    23

    Default

    OK, that would make sense due to the fact it feels like it pulls 2x as much as before. As I said above, do you think that a droop, rideplate, and shoe would make a difference? I'm used to the drag racing scene, im new to this water stuff.

  10. #8
    tintingsandiego krusn56's Avatar
    Join Date
    Oct 2008
    Location
    San Diego
    Posts
    1,063

    Default

    I recently had my motor built by Bostick with a bit less HP than yours. He rebuilt my pump as well adding a 9 vain aggressor/straight snoot. While cruising now its about 2-300 rpm's less to be at same speed. I added a bolt on shoe/plate from Duane HTP which helped out more in top end for control and attitude. I never gps'd my boat before or after but definitely can tell its out of the hole faster, rides better and has picked up top speed. I feel all the add ons led to each giving a small improvement and in the end a big improvement over all.
    Made In The Shade

    Custom Window Tinting

  11. #9
    Senior Member
    Join Date
    Sep 2012
    Posts
    264

    Default

    Rideplate and shoe might give you a few more mph.

  12. #10
    Resident Ford Nut Sleeper CP's Avatar
    Join Date
    Dec 2007
    Location
    San Diego County
    Posts
    10,072

    Default

    If you run it at ski speed (3,000-3,200) for a few seconds then run it WOT for 8-10 seconds you're probably 98-99% done

    "Dark Sarcasm"
    Going fast is only half the fun ... what you make go
    fast is the other half.
    " A Government big enough to give you everything you want is big enough to take away everything you have"

  13. #11
    Senior Member GT Jets's Avatar
    Join Date
    Jun 2008
    Location
    Morgan Hill
    Posts
    2,234

    Default

    Quote Originally Posted by Bobbylisa View Post
    Rideplate and shoe might give you a few more mph.
    Then again, may not... It definitely wont hurt anything.
    GT


    Quote Originally Posted by Quickjet View Post
    Put a 300 on the back of it, Flywheel it and a nosecone. $15,000 later you'll have a 65 mph pile of shit......

  14. #12
    21' Bahner Sport ATKpilot's Avatar
    Join Date
    Jun 2008
    Location
    CA
    Posts
    125

    Default

    Quote Originally Posted by mikevoisine View Post
    Hows it goin, I recently rebuilt a 78 tahiti super tiger and installed a big block chevy I built for it, estimated around 500hp. I rebuilt the jet drive with an a impeller loader scoop with a place diverter and red insert cone. So far ive held it wide open for about 6 to 7 seconds and hit 63 MPH on a gps. I can spin the impeller to 5200 rpm constantly so my HP estimate is about right. The question is from your experience, how long should it take me, holding it wide open, to hit the max speed, and what should I be seeing for a max speed with this type of hull. Thanks.
    Wow, your boat brings back a lot of memories, that was my very first boat that I bought myself. I had my engine built by Jim Pisciotta Racing and it had a few more ponies than you have and it ran 66=68 on a speedo, mind you that was way before GPS. I had a blast with it though and learned a lot about jets.That damn motor ripped the torque side of 1/4 stringer right out of the floor though. Luckily my Dad knows a lot about fiberglass and repair and we fixed it correctly. I sold it to a guy that loved it, so all good. Like the others have said, you are about right were you are going to be...

    Just have fun and enjoy it
    Last edited by ATKpilot; 07-28-2013 at 09:03 PM.

  15. #13
    Senior Member uniboarder's Avatar
    Join Date
    Dec 2012
    Posts
    480

    Default

    That's running pretty good for a cruiser! Use the money you have to buy a smaller hull over pump parts. Then you can have a family boat and a runner!

  16. #14
    Senior Member ol guy's Avatar
    Join Date
    Mar 2008
    Location
    Lake Elsinore Ca
    Posts
    3,812

    Default

    Quote Originally Posted by mikevoisine View Post
    Hows it goin, I recently rebuilt a 78 tahiti super tiger and installed a big block chevy I built for it, estimated around 500hp. I rebuilt the jet drive with an a impeller loader scoop with a place diverter and red insert cone. So far ive held it wide open for about 6 to 7 seconds and hit 63 MPH on a gps. I can spin the impeller to 5200 rpm constantly so my HP estimate is about right. The question is from your experience, how long should it take me, holding it wide open, to hit the max speed, and what should I be seeing for a max speed with this type of hull. Thanks.
    I played with a 1973 tahiti years ago and for shits and giggles went out and ran at an NJBA race at bluewater-Stock 454 with manifold, carb and headers. I won that race and the boat ran dead-nuts at 69.7 mph every pass. I will add I did alittle (on the trailer) bottom work on it to free it up a pinch. No droop jc stock pump no ride plate or diverter and that boat was all done in about 500 ft then it was light a smoke have a beer and go thru the traps about 8 or 10 seconds later. It was fun and surprised me how well it ran for a heavy ass boat!

+ Reply to Thread
Page 1 of 3 1 2 3 LastLast

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in


Tags for this Thread

Digg This Thread

Posting Permissions

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

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95