Search:

Type: Posts; User: Jimboat; Keyword(s):

Search: Search took 0.01 seconds.

  1. Replies
    4
    Views
    3,296

    Depends on what class you're interested in, but...

    Depends on what class you're interested in, but Bob Dillon has some good plans for GT and Sport C class boats.
  2. Replies
    2
    Views
    3,173

    Thanks, Ron. Technical articles available here:...

    Thanks, Ron. Technical articles available here: aeromarineresearch.com/performance_articles.html
  3. Replies
    27
    Views
    22,378

    dvd....with regard to your original...

    dvd....with regard to your original question...(sorry i seem to have missed the question, first time through)... sure! there's a possibility of dynamic instability at this kind of speed. ...
  4. Replies
    27
    Views
    22,378

    What racing class is that?

    What racing class is that?
  5. Replies
    27
    Views
    22,378

    Sounds like fun to me! Dynamic stability always...

    Sounds like fun to me! Dynamic stability always important in design and setup of tunnel boats going fast. depends on design details and setup, of course.
  6. Thread: Bob Switzer

    by Jimboat
    Replies
    0
    Views
    1,082

    Bob Switzer

    A sad day in powerboat history. I just heard that Bob Switzer, hero and friend, passed away on Friday December 29, 2017. A true hero. Will be remembered as one of the really true innovators,...
  7. Replies
    26
    Views
    6,549

    here is an article on 'Rooster Tails...

    here is an article on 'Rooster Tails'
  8. Replies
    28
    Views
    19,238

    BYOBoat - it sounds like you've got a pretty good...

    BYOBoat - it sounds like you've got a pretty good handle on using TBDP to optimize your performance. Good job! I think you're on the right track with the ideas you're following in your explanations...
  9. Replies
    28
    Views
    19,238

    Your boat's looking great! Any amount of 'hook'...

    Your boat's looking great! Any amount of 'hook' in main running surfaces (sponsons) will normally reduce top speed a little bit. It will also reduce trim somewhat and potentially preclude/delay...
  10. Replies
    4
    Views
    2,214

    Sounds like a fun project!

    Sounds like a fun project!
  11. Replies
    5
    Views
    3,554

    Update - TBDP/VBDP performance software Version 8...

    Update - TBDP/VBDP performance software Version 8 now includes spray rails, lifting strakes and trim tabs. (plus a bunch of other new features!)

    Spray Rails are normally on chine/sheer and can...
  12. Replies
    27
    Views
    22,378

    ice-spy - you're sure right to say that there are...

    ice-spy - you're sure right to say that there are many different tunnel hull designs around! There definitely many factors that can make any tunnel hull design perform at it's best, though. The...
  13. Replies
    19
    Views
    4,069

    Yup, for sure! Sounds like you're much too low. ...

    Yup, for sure! Sounds like you're much too low. Raise motor, make sure you're still getting water (get a pressure gage). Test for new surfacing props.
  14. Replies
    15
    Views
    4,471

    Joe - as i suggested, nearly every hull design is...

    Joe - as i suggested, nearly every hull design is a "compromise" of many performance desires/expectations. Given an existing vee hull design of weight/size/power - the best pad design is a compromise...
  15. Replies
    15
    Views
    4,471

    Every hull design/setup has an optimum pad design...

    Every hull design/setup has an optimum pad design (width, length, depth) for the desired performance expectations. The tricky part of the design is that the characteristics change at each velocity...
  16. Replies
    11
    Views
    4,332

    nice boat! if you size the pad correctly, it...

    nice boat! if you size the pad correctly, it should be a winner!
  17. Replies
    15
    Views
    4,471

    no problem, chris. give me a call or PM me, if...

    no problem, chris. give me a call or PM me, if you want to discuss.

    /jim
  18. Replies
    15
    Views
    4,471

    The size of the pad should be sufficient to...

    The size of the pad should be sufficient to provide greater portion of dynamic lift of the hull. A wider pad is more efficient, but also harder ride. Optimum width and length are sized based on...
  19. Thread: Rouen 24 hours

    by Jimboat
    Replies
    36
    Views
    10,372

    Way to go, Tammy! Great drive!

    Way to go, Tammy! Great drive!
  20. Replies
    81
    Views
    20,746

    1. what is your rpm currently, vs. max rpm of...

    1. what is your rpm currently, vs. max rpm of engine?
    2. can you send me a picture of your hull running at current top speed?
  21. Replies
    26
    Views
    4,697

    Nason - sorry to avoid the 'quick' answer...to...

    Nason - sorry to avoid the 'quick' answer...to make performance assessment of your 2 boats, we'd need details of each design, and power/weights for each setup, and would then do a dynamic performance...
  22. Replies
    26
    Views
    4,697

    Agree completely with Yellowjacket. A pad can...

    Agree completely with Yellowjacket. A pad can really make a vee hull fly. Each pad should be designed particularly for the hull, power, setup and expected use (speed), however. If not enough pad, the...
  23. Replies
    9
    Views
    7,429

    The sizing of a pad can be designed for the...

    The sizing of a pad can be designed for the specific hull dimensions, weight, HP, etc. (Duplicating a pad from one hull on a different hull might not work out as well).

    A proper pad design...
  24. Replies
    62
    Views
    21,148

    Looks good! is that the tunnel design that we...

    Looks good! is that the tunnel design that we corresponded about recently? The modelling we did showed some good results. Glad that the testing is showing same. Send me some details of your...
  25. Replies
    13
    Views
    4,765

    Sam - this must be one of the very first...

    Sam - this must be one of the very first hydraulic trim systems! who do you credit with inventing it?
  26. Replies
    13
    Views
    4,765

    what year of manufacture do you think that trim...

    what year of manufacture do you think that trim piece is, Sam?
  27. Replies
    4
    Views
    3,068

    zul8tr - yes. you're right. I've corrected the...

    zul8tr - yes. you're right. I've corrected the website (typo). I am not sure which version of TBDP software you have, but your TBDP User manual reflects proper info (but no typo!). thanks.
    Just give...
  28. Replies
    4
    Views
    3,068

    Sure... Velocity Optimize – [Trim Angle...

    Sure...

    Velocity Optimize – [Trim Angle specified, Maximum Limiting Velocity determined] - use to get an estimate of the velocity that is achievable at a specified trim angle (WAngle) OR (with...
  29. Replies
    62
    Views
    21,148

    Mark - your new design looks very innovative. i'm...

    Mark - your new design looks very innovative. i'm glad that the TBDP software has worked so well for you. Your hull is a great looking boat! Good work!

    I note you're using an "s-shaped" aerofoil...
  30. Replies
    45
    Views
    9,772

    National Geographic "Thrill Zone - Extreme Powerboats"

    The National Geographic special "Thrill Zone - Extreme Powerboats" is showing again this year on NatGeo channel - next show is Thursday, September 27, 2007, at 08A. Some descriptions were given in a...
  31. Replies
    8
    Views
    3,912

    Jimbo McConnell drove a Mod U laydown design...

    Jimbo McConnell drove a Mod U laydown design once, i think the design concept was Jack Leek's and was built by Wilbur McDonald. In Canada, Spencer Dunn drove the same design, built by Lorne Pinel....
  32. Thread: Cool Fuel

    by Jimboat
    Replies
    18
    Views
    3,361

    cool cans in U & S-class tunnels

    OMC factory tried cool cans in U-class boats in 70's on V4's. They used dry ice in an aluminum can, with fuel running through a coil inside the can. i don't really recall any of the other details,...
  33. Thread: hydro ID?

    by Jimboat
    Replies
    5
    Views
    2,218

    Barry - WOW! You're a real detective. that...

    Barry - WOW! You're a real detective. that should be sufficient info. thanks a lot!
  34. Thread: hydro ID?

    by Jimboat
    Replies
    5
    Views
    2,218

    Unidentified?

    Boy! I thought you'd get it for me, Ron. The boat was originally in Ohio. The owner said the company that made it made only 2 of them. Current owner is trying to identify the maker. It is...
  35. Thread: hydro ID?

    by Jimboat
    Replies
    5
    Views
    2,218

    hydro ID?

    Does anyone recognize this hull? builder?
  36. Thread: Hi Ron!

    by Jimboat
    Replies
    3
    Views
    2,532

    Thanks, Ron!

    Ron - congratulations on getting this forum going! There are few people that have the history and memory for real boat racing, as you do! We will all make this one of our regular 'stops' for sharing...
Results 1 to 36 of 46