IMPBA Outboard question

[legendscar24]

Guys,

Does IMPBA have a stock B outboard class??

Mike.

 

[Bob Kensill]

No,we have a "B Sport Tunnel" class. It is basically a "stock appearing" class with no motor tear down.

 

[legendscar24]

Stock appearing meaning what? are there hull limitation, engines limitations, I read the rule book and still don't understand, NAMBA is easier to understand thats for sure, thanks for your help.

Mike.

 

[VansRacing]

Mike,

It is actually very simple. -20 Sport tunnel-

You can not change the bore, stroke or exhaust hole diameters and you can not exceed a .312" bore carb. (for the sport 2o tunnel class) but you can modify the skeg size and you can polish it. You can use any type adjustable engine mount you want.

You can change anything inside the engine that can not been seen from the outside that doesn't violate the rules above or exceed the max carb bore of .312" (for Sport 20 tunnel)

We love it. Simple...Tommy Lee and Rod Geraghty wrote them and they make life simple for us all.

-Carl,

 

[Jerry Dunlap]

Re: B Stock Class

B Stock in NAMBA is a 7.5cc or 45 ci size engine. B Class in IMPBA is 3.5 cc or 21 ci. Both organizations should just toss the "Alphabet Soup" out the window and use numbers. Both groups agree on Sport 21 and Sport 40 Hydro. Seems like we could agree on 21/40/60/90 clases for nitro boats. Oh my gawd!!! NAMBA and IMPBA agreeing on something?? With global warming, maybe Hell could start to thaw.

JD

 

[legendscar24]

Does IMPBA has a 7.5 outboard tunnel hull class

Thanks,

Mike.

 

[Don Ferrette]

Does IMPBA has a 7.5 outboard tunnel hull class

Thanks,

Mike.

Yup, it's called D tunnel.

 

[VansRacing]

Re: B Stock Class

B Stock in NAMBA is a 7.5cc or 45 ci size engine. B Class in IMPBA is 3.5 cc or 21 ci. Both organizations should just toss the "Alphabet Soup" out the window and use numbers. Both groups agree on Sport 21 and Sport 40 Hydro. Seems like we could agree on 21/40/60/90 clases for nitro boats. Oh my gawd!!! NAMBA and IMPBA agreeing on something?? With global warming, maybe Hell could start to thaw.

JD

Sounds good to me JD but getting it done would spark off the 2nd civil war!

Most tunnel racers around here call the classes 20 tunnel, 40 tunnel and 60 tunnel anyway.

Not sure why the ABC's are thrown in there.

Hey, I got a question for the Hobbico team and stock holers...(and I know you and Russ have probably been asked this question 1,000 times) but, Question # 1,001: When is O/S going to build a 7.5cc outboard?

Are they waiting for us ole timers to all die off before they release it? LOL Well, why don't you and Russ go see the great OZ and ask him when they plan to build the O/S 7.5 Outboard so can all get excited???

-Carl,

 

[Jerry Dunlap]

Re: O.S 7.5 OB

That would be one sweet engine. But, I have no idea if it will ever happen.

JD

 

[bzubee]

I think using the numbers would be much easier for all to understand this way IMPBA could still keep the "A" and "C" classes too.

 

[Grimracer]

Re: B Stock Class

B Stock in NAMBA is a 7.5cc or 45 ci size engine. B Class in IMPBA is 3.5 cc or 21 ci. Both organizations should just toss the "Alphabet Soup" out the window and use numbers. Both groups agree on Sport 21 and Sport 40 Hydro. Seems like we could agree on 21/40/60/90 clases for nitro boats. Oh my gawd!!! NAMBA and IMPBA agreeing on something?? With global warming, maybe Hell could start to thaw.

JD

Hallelujah... say if Jerry.. say it again and again untill we .............all...... get it..

Go jerry go

Grim

 

[legendscar24]

WTF D tunnel oh man, I agree totally 3.5 tunnel 7.5 tunnel and so on. Cool so is D tunnel a non modified class???

 

[Russ Williamson]

Hey, I got a question for the Hobbico team and stock holers...(and I know you and Russ have probably been asked this question 1,000 times) but, Question # 1,001: When is O/S going to build a 7.5cc outboard?

Are they waiting for us ole timers to all die off before they release it? LOL Well, why don't you and Russ go see the great OZ and ask him when they plan to build the O/S 7.5 Outboard so can all get excited???

-Carl,

Q#1001; All I can say is......yes.............we have been asked that question a 1000 times

Seriously though, I've met with O.S. this year and with the increase in the activity in the marine market this summer; they are paying more attention to what is going on.

Before a 7.5 is ever made, the 3.5 must be upgraded, as it is the most popular class in outboards.

At this time, not sure if anything will be done to the 3.5, but it has been/was highly recommended. Who knows, maybe somebody else will come out with a 7.5 in the years to come.....

Rw

 

[VansRacing]

The O/S 3.5cc outboard was designed by someone who really understood what was needed from the flywheel to the prop nut. That engine is unreal right out of the box! Don't get me started toot'n that horn....I should be a O/S outboard salesman! I love them!

 

[GMCSW7]

WTF D tunnel oh man, I agree totally 3.5 tunnel 7.5 tunnel and so on. Cool so is D tunnel a non modified class???

There is NO non modified Tunnel class in IMPBA even; 20 Tunnel (B Tunnel) 40 Tunnel (D Tunnel) and etc... are all (most of the time )heavely moded classes.

Steve

 

[Grimracer]

Sounds good to me JD but getting it done would spark off the 2nd civil war!Most tunnel racers around here call the classes 20 tunnel, 40 tunnel and 60 tunnel anyway.

Not sure why the ABC's are thrown in there.

Carl,

Carl,

The IMPBA adopted the letters from the old airplane free flight days. However unlike free flight there is no 1/4A or 1/2A in model boating… We just started off with A.

Also just for a quick clarification.. and this is important at least for now is that we call it Sport 21 Tunnel.. I have had guys confused by saying Sport 20 tunnel. They hear Sport 20 and sometimes not the tunnel.. Can you see the confusion.. Minor.. I agree.

Because i have followed this format for a long time (im a nut for the old aircraft stuff) IMPBAs system, as nutty as it seems, makes since to me. How NAMBA moved the displacements –vrs- numbers up a engine size is a mystery to me. Im sure someone knows more about this then me.

If it were up to me i would dump the old lettering system for a new easer to understand prospective for the new boater.

12 Tunnel

20 Tunnel

40 Tunnel

60-80 Tunnel, Hydro, Mono whatever... you get the point.

25 gas hydro.. whatever the gas dudes need is cool with me.

for FE it would be

8 cell hydro or maybe 10 volt Hydro..

12 cell hydro, mono, sport hydro and the like. I feel that in a few years.. maybe now.. brushed motors will be a thing of the past anyway.. so to heck with motor call out. Want a spec class.. have at it. call it LSH.. or O as they do now and leave as is..

GMC,

You are right there is no STOCK anything in the IMPBA.. just stock appearing..

Grim

 

[legendscar24]

Thanks Steve that was my question.

Mike

 

[Bob Kensill]

So mike,is this the beginning of a board proposal?

 

[Grimracer]

Bob.. when i can free up some time after the move... hum... . . .

Sure looks to me like it could use a good review.

Mike

 

[bzubee]

Ihave asked John Equi (head of Tech committee) to look into switching to a numerical system the Gas classes are already that way. LS 27 ect. I'll mention it to Randall also