Hydroplane help needed.

[Josh Stollfuss]

My SS45 is not getting up on pipe. I'm running a PT SS45 its' right about 10 pounds with out fuel. I'm running a CMB .45 pruple head Hydro engine with a CMDI parabolic pipe set at 9.5 inches. I've been running a Props 4 U X450 2 blade that has been cupped. It will not quite pull the RPM's needed to get it up on pipe like it should. It gets close and seems like wants to come on pipe but won't. If I lean the needle down it will run 2-3 laps then dies, but even then doesn't get up on pipe like it should. (doesn't burn out the plug) The boat is still a little wet in the water. What do you guys think my next steps should be? Shorten the pipe a little? Go to a non-cupped prop? Raise the strut?? Any suggestions would be appreciated! (The boat in question is the one pictured in my avitar).

Thanks!

Josh-

 

[Don Ferrette]

My SS45 is not getting up on pipe. I'm running a PT SS45 its' right about 10 pounds with out fuel. I'm running a CMB .45 pruple head Hydro engine with a CMDI parabolic pipe set at 9.5 inches. I've been running a Props 4 U X450 2 blade that has been cupped. It will not quite pull the RPM's needed to get it up on pipe like it should. It gets close and seems like wants to come on pipe but won't. If I lean the needle down it will run 2-3 laps then dies, but even then doesn't get up on pipe like it should. (doesn't burn out the plug) The boat is still a little wet in the water. What do you guys think my next steps should be? Shorten the pipe a little? Go to a non-cupped prop? Raise the strut?? Any suggestions would be appreciated! (The boat in question is the one pictured in my avitar).

Thanks!

Josh-

Josh do you have any props that are a little smaller or not cupped? I always start out with a smaller prop to dial a boat in & then work from there. The 9.5" pipe length might be a touch short for a cupped x450 on a 10 pound boat. FWIW- my favorite sport 40 prop is a x646/3 with as much cup as you can safely put in it, very fast & will let the motor sing at a short pipe length like 9.5".

 

[Josh Stollfuss]

I have a stock X450 2 blade, X450 3 blade, a X447 3 blade with a slight cup, a Prather 230 and 235. I was thinking about trying the stock 450 2 blade? Do you think 9.5 on the pipe length is too short? Should I add an 1/8 to the pipe length?

Josh-

 

[Don Ferrette]

I have a stock X450 2 blade, X450 3 blade, a X447 3 blade with a slight cup, a Prather 230 and 235. I was thinking about trying the stock 450 2 blade? Do you think 9.5 on the pipe length is too short? Should I add an 1/8 to the pipe length?

Josh-

Run the x447/3 first to get you going. I prefer 3 blade props on scales & sport hulls as they have a little more lift to carry the boat thru the corners. The fact that you have the rear wings puts more weight on the prop also. The 9.5" pipe length will really let that motor sing like it should, you just need to prop to match it. B)

 

[Josh Stollfuss]

I thought I was close on the pipe set up, But I think Don is right I just have more prop then a heavy boat like that can pull. I'll try the X447 tonight.

Josh-

 

[Don Ferrette]

I thought I was close on the pipe set up, But I think Don is right I just have more prop then a heavy boat like that can pull. I'll try the X447 tonight.

Josh-

Josh the cupped x646/3 that I ran came from Mark Sholund, I know he'll remember what he did. With a stock MAC45, parabolic pipe at 9.5" & the x646 my ss45 I had ran 61 on radar in heat race trim in an early spring test session, solid upper 50's rest of time. B)

 

[Josh Stollfuss]

Thanks Don, I'd be happy if I could get it intothe Mid 50's right now!

Josh-

 

[SayMikey]

Thanks Don, I'd be happy if I could get it intothe Mid 50's right now!

Josh-

my pipe length is a pinch over 10 i run conservative a stock x450 will get right up and take you to 50 the ticket in the midwest is a 1455 d/t and pitched.We pitch it till it wont launch and then back up a hair. mines picco powered

 

[Josh Stollfuss]

One thing I need to get straight in my mind on pipe lenght, Longer = more torque? Shorter = more RPM?

Josh-

 

[anthony_marquart]

That's the way I understand it.

One thing I need to get straight in my mind on pipe lenght, Longer = more torque? Shorter = more RPM?

Josh-

 

[user 115]

I thought I was close on the pipe set up, But I think Don is right I just have more prop then a heavy boat like that can pull. I'll try the X447 tonight.

Josh-

I would try the pipe at 10.5 to start. I ran 10.25 with a CMB 45 and AB nitro pipe pulling a 1455/3 on a AC Sport 40. I don't know how the parabolic will react with the CMB but 9.5 seems awfully short. I would try a 450/3 as well to start.

 

[Don Ferrette]

I thought I was close on the pipe set up, But I think Don is right I just have more prop then a heavy boat like that can pull. I'll try the X447 tonight.

Josh-

I would try the pipe at 10.5 to start. I ran 10.25 with a CMB 45 and AB nitro pipe pulling a 1455/3 on a AC Sport 40. I don't know how the parabolic will react with the CMB but 9.5 seems awfully short. I would try a 450/3 as well to start.

The parabolics typically run shorter than you're used to.

 

[Josh Stollfuss]

That's what I was thinking... 9.5 inches is recommended pipe length off the CMDI web site. 10-10.25 inches seems aweful long. I have a Mac .45 in my D mono that runs the same parabolic pipe set exactly at 9.5 inches and it screams. That's why I started at 9.5 on this Hydroplane, but every boat is different.

Josh-

 

[Duck899]

A little longer with the pipe would have been the place to start. Gradually shorten it as you go....I ran an octura X-646/3 for years. Don't be fooled by the smallish size of the 646/3.....It will go like a raped ape and be easy to set up. Not only that, get yourself a pitch guage and watch what small changes in cup do to this prop......

 

[Josh Stollfuss]

I'm going to run it tonight afterwork, So I'll post tomorrow on worked or didn't work.

Josh-

 

[Josh Stollfuss]

I ran the hydroplane last night. I ended up 1st trying the Prather 230 prop I had. I figured if it couldn't pull that prop I had other issues. But it ran ok with the prather 230 and it came up on the pipe after a couple of needle adjustments. I put the cupped X447 on it and it ran really nice. I played with the pipe lenght and ended up about an 1/8 shorter. It was just slightly over 9.5 inches now it is about 9-7/16" and it just screams.. Now I opened up a new set of probelms, now it hops in the corners.. What do I need to do to correct that? Turn fin adjustments or strut depth??

Thanks!

Josh-