IMPBA Sport 20 rules

[Don Ferrette]

John Equi asked me to post the preliminary IMPBA sport 20 rules as follows-

Proposal to add SPORTSMAN 20 HYDRO to rule book.

Page H7 revision

Sportsman 20 Hydro (Sport 20 Hydro)

1 Boat must be inboard powered.

2 Hull must be a three (3) point hydroplane configuration and resemble a Limited

or Unlimited hydroplane design of past or present.

Hulls NOT permitted: outrigger, modified outrigger, tunnels, or canard hulls.

3 Boat must have a name, or sponsors name, or logo, or a racing number affixed to

the hull. (a local or national or fictitious sponsor name is acceptable)

4 Hull shall have a minimum length of 27 inches, and a maximum length of 35 inches.

5 If the bow is recessed behind the tips of the sponsons, that recess shall be no larger than 25% of the overall length of the boat. (refer to Sport Hull Configurations)

6 Boat must have a driver in open cockpit or simulated enclosed cockpit

7 NO part of the strut may protrude behind the transom of the boat, or have a width greater than 9/16 inch or a length longer than 3 inches.

8 See Sport Hull pictorial for clarification of Sport Hull Configurations.

Engine Specifications

1 IMPBA class B engine allowed in SPORT 20 HYDRO

2 Twin engine installations are NOT allowed in SPORT 20 HYDRO

General Rules

Racing to be conducted following current IMPBA Contest and Racing Rules, racing

procedures and format.

 

[Paul Pachmayer]

Hi Don,

7 NO part of the strut may protrude behind the transom of the boat, or have a width greater than 9/16 inch or a length longer than 3 inches.

That's not how I recall reading the rules on sport 20, I remember reading that hardware (strut) mounted on the transom would be allowed? Reason being several people with running boats already had them setup with transom mounted hardware.

Paul.

 

[Paul Pachmayer]

Hi Guys,

Found it.

http://www.intlwaters.com/index.php?showtopic=7950

Paul.

 

[bzubee]

Paul, what you read is what the Racers Group agreed on for the rules for the 2005 Internats. What Don posted is what may become the official rules for the class unless members want to modify them. There will be a request for Feedback from John Equi in his article in the March Roostertail.

 

[Jerry T]

That's how District 4 proposed the rules a couple years ago, basically just like Sport 40. Keep the strut under the transom. That's where it belongs.

 

[P THOMAS]

That's how District 4 proposed the rules a couple years ago,  basically just like Sport 40.  Keep the strut under the transom.  That's where it belongs.  

84605[/snapback]

​

There was a proposal signed and sent to the IMPBA? what happen to it?

We need to get the members to sign the proposal and send it to the dist directors per the rule book, to get the IMPBA going on this.

 

[Jerry T]

Phil, that's what I thought, and it was like the sport 40 rules. Please correct me if i am wrong.

Thanks

Jerry

 

[Don Ferrette]

That's how District 4 proposed the rules a couple years ago,  basically just like Sport 40.  Keep the strut under the transom.  That's where it belongs.  

84605[/snapback]

​

Yup, I'll agree to that. B)

 

[shoboat]

Boaters,

I have one simple question: Why do ALL THE Sport classes have to follow

1/8th Scale with the strut rule? I think this is SILLY. You should put your

strut on your boat where you want to,everyone already agrees it doesn't

affect the performance, so what is the big deal? Sport 20 should not be

like 1/8th Scale and Sport 40. This is the way I see it. :unsure:

Let's Race, Not Argue,

Mark Sholund

 

[dave roach]

Putting the strut back behind the transom will change the boats. It will thank the boat is longer.

my .02 cents

 

[Plan D]

I think the idea is to look some what like the full sized boats that have the strut and prop under the hull

 

[shoboat]

Plan D,

Have you looked at the real boats lately? Notice where the strut and rudder

placements are?

Dave,

Longer is better for performance, isn't that why we race?

Just Looking Outside The Box Fellas,

Mark Sholund

 

[Terry Flynn]

Why is it that if there going to follow the rules of 1/8 scale on the placement of the strut and rudder. then why would they rule out the Winston Eagle Lobster and the Circus Circus canard? These boats are real boats that raced. If there allowed in 1/8 scale why not in sport 40 and sport 20?

Terry

 

[shoboat]

Terry,

For some odd reason, people think that these boats have a unfair advantage

because of their design features. What is puzzling is that anyone can build

one,so it is not fair to exclude these from Sport 40 or Sport 20,but these are

the rules that we follow in IMPBA. I just think that Sport 20 should be a little

more open-minded towards design. Maybe if the IMPBA wants to build up our

boat racing membership, they should be a little more open-minded on this newest

class?

Good Luck,

Mark Sholund

 

[bzubee]

Please read the March issue of the Roostertail it has Phil's propsal for comments to your district Direcotr or John Equi on the rules. I feel the same way you do Mark btu I am only one vote. When the time comes that is when you can vote how you feel.

Bill Zuber

 

[Grimracer]

Terry,
For some odd reason, people think that these boats have a unfair advantage

because of their design features. What is puzzling is that anyone can build

one,so it is not fair to exclude these from Sport 40 or Sport 20,but these are

the rules that we follow in IMPBA. I just think that Sport 20 should be a little

more open-minded towards design. Maybe if the IMPBA wants to build up our

boat racing membership, they should be a little more open-minded on this newest

class?    

Good Luck,

Mark Sholund

84753[/snapback]

​

Mark,

Good questions... however.. what would the strut on the back realy gain you? Faster.. so.. better handling? then what? Another boat set up the same way?

I get very confuesed each time this comes up.. most will say and heck i even agree.. the boat might be a better handling boat with the strut on the back.. my point is... OK... so it does.. does this make for better racing? or whats the point of it.. whats the real need for change? For the sake of change?

Not crabing i just dont get it...

ROCK ON

Grim

 

[Paul Pachmayer]

Hey Guys,

Mike,

Not crabing i just dont get it...

Several good reasons to allow the strut to be hung off the back of the boat.

#1, this is the biggest as I see it, ease of installation!

#2, strut adjustments are mush less a hassel.

#3, no hole in the bottom of the hull, less water intrusion.

#4, the ability to "fine tune" the boat.

#5, the stuffing tube doesn't need to be a 2 piece affair, simpley epoxy it into the hull.

The idea of having the strut mounted under the hull is silly and "old school". Sorry guys but I have never heard a good reason behind that rule, other than in 1/8th scale. And yes, several full size ULs are now running with with the strut hanging off the transoms, hmm, must be something to it. I'm glad the FE section of the rules were keen enough to allow any strut placement.

Paul.

 

[Watercadet]

The Phil Thomas Sport 20 is a sweet looking boat. In the few years that I have been folowing the Unlimmiteds and UL closely, I have never seen a boat that looks as futureistic. It has little in common with it's 1:1 scale counterpart in the apperance department. So if we are wondering away from scale apperance what is a minor change like moving the strut to the transom? The sport 40 II class in my District has been dubbed Unlimited Lites. OK lets make them scale. The "real" boats have struts off the back.

Adam

 

[Grimracer]

Hey Guys,
Mike,

Not crabing i just dont get it...

Several good reasons to allow the strut to be hung off the back of the boat.

#1, this is the biggest as I see it, ease of installation!

#2, strut adjustments are mush less a hassel.

#3, no hole in the bottom of the hull, less water intrusion.

#4, the ability to "fine tune" the boat.

#5, the stuffing tube doesn't need to be a 2 piece affair, simpley epoxy it into the hull.

The idea of having the strut mounted under the hull is silly and "old school". Sorry guys but I have never heard a good reason behind that rule, other than in 1/8th scale. And yes, several full size ULs are now running with with the strut hanging off the transoms, hmm, must be something to it. I'm glad the FE section of the rules were keen enough to allow any strut placement.

Paul.

84773[/snapback]

​

Sorry Paul .. i still do not get it.. not digging on yea its just the way my brain works things need to make sense to me..

#1, Ease of instation.. noting hard about placing it underneath.. besides no need to make a hole for the strut to pass through.. just depends on the strut..

#2, strut adjustments are mush less a hassel... relative.... what hassle.. i dont see it.

#3, no hole in the bottom of the hull, less water intrusion... again depends on the strut. Shims are amazing in here tuning ability and there ability to reproduce..

#4, the ability to "fine tune" the boat... fine tuning the strut is cool but we have lots of other places to fine tune.. the prop is a good start. And again (copy and paste) Shims are amazing in here tuning ability and there ability to reproduce..

#5, the stuffing tube doesn't need to be a 2 piece affair, simply epoxy it into the hull... opposite here.. the advantage of an off the transom strut is the two peace stuffing tube.

Old school... maybe.. and again I just want to say it matters little to me either way.. but to do it because the full scale boats are doing it..? When we have a true UL class... lets make it a true scale UL class... for now its a sort of stand WAY OFF full body style hull.. its not even stand off scale.

When we started racing b class sport boats in Dist 4 it was called Scale Twenty.. The boats were to look like real boats and or me patterned and painted like a real boat.. 10 of the 20 guys liked the idea.. non of them wanted to put in the work to make the boat look real.. Slap a fricking tunnel cowl on a pay n pac kit and race it..YUK.. that is what they wanted and that is what they got.. My first thoughts were to heck with this going to IMPBA as a class.. let the clubs grow this.. that Is where the growth is going to come from. Problem is that when you people wanting hulls,,, and guys like Phil T saying we can do that but what are the rules?.. now we have a problem. IMPBA to the rescue..

Im sure that this will all come out in the wash but if the strut and or the perceived importance of its location is going to be the topic of intimidation for somebody joining in to have some sport boat fun.. well… good thing we have monos and tunnels too…

I can not wait to get my new sport 20 boat on the water this year.. its going to be FUN TO RACE… for sure. YEAAA HAAAA

Grim

 

[Paul Pachmayer]

Hi Mike,

I used the full size UL comparison because that's what I always hear about the "under the hull" strut, real boats don't do it.

#1, Ease of instation.. noting hard about placing it underneath.. besides no need to make a hole for the strut to pass through.. just depends on the strut..

Mike, your a class act when it comes to building and racing, with that in mind I'm calling you out.

We take two of Phil's SS 20 hulls and 2 hardware setups, then head to head see who gets the boats hardware setups installed first. I bet you the price of the boat that I'm done first, and cleanly. You really think a fixed strut is as tunable as one hung off the transom?! I'm guessing your refering to something like the Luminar Pro Boat?

I would like to see a setup like a fixed strut under the hull have over a half inch of lateral and or angle adjustment. While your messing with shims I'm making minute adjustments by loosening 1 cinch bolt. Water gets rough, I add a 1/4 inch depth to the strut and help pin the nose and it takes all of 30 seconds to do. How many shims will that take?

#4, the ability to "fine tune" the boat... fine tuning the strut is cool but we have lots of other places to fine tune.. the prop is a good start.

A prop or shims wont get that strut an extra half inch or so aft of the transom.

#5, the stuffing tube doesn't need to be a 2 piece affair, simply epoxy it into the hull... opposite here.. the advantage of an off the transom strut is the two peace stuffing tube.

I'm not sure I follow you, a 2 piece stuffing tube?

Paul.