For Don F., Scott S., And Rod G.

[Kevin_R_Clark]

Don F.,

Finally got out. Put the 260 on and left everything else alone. Miss B wouldn`t get on the pipe. Ran 50% Red Max. Anyhow I had a bunch of new boats to shake down so we only tried adjusting the needle. Plus the pond we used today was kind of small and I was worried that it would jump on the pipe and cause a wet spot somewhere. My buddies Eagle does that and on this pond it is all you can do to keep it off the shore. I am thinking I need to play with the pipe length but would like to hear your thoughts also. Spokane is at 2000 ft alt., and it was just a perfect 70 degree day.

Scott S.

I put the one with the Modded water jacket and Black Picco carb, Motor # 2 in my A hydro. It is worth mentioning that I had it set up with the same type -P5 EXR- and it ran great. All I did was swap motors and go from 50% to 65 %. Anyhow it will get on the pipe but the throttle response is terrible. I will say that on the stand it is very hard to get a feel for the needle and the old motor was the same way. i.e. it did not like to clear out and was very unresponsive when you open the throttle. I suspect it is a trait of these motors or my set-up. Now when in the water it is a different story. The old motor was a rocket and behaved normally. Old number 2 responds to needle adjustments and is comparablely fast but I have almost no throttle control. i.e. just as fast at half throttle as it is wide open. I suspect that the set-up either does not like the carb or the OPS 3280 pipe. What do you think.

Rod G,

Hey I got one right out of three. Not to bad for first day. Put the Rossi in an AC Mono and it screamed right off that bat, so much so we toned the tune up down a little. Ran very comparable to the Bluehead Picco we took out. Still haven`t gotten to the outboards you did for me, my daughter was complaining so I had to get her boat going first. Anyhow thanx for the great work!!!!

 

[Don Ferrette]

" Don F.,

Finally got out. Put the 260 on and left everything else alone. Miss B wouldn`t get on the pipe. Ran 50% Red Max."

Hey Kev-

I didn't send a 260?? I sent two props Octura X462 & X465. Start with the X462 set pipe at about 12 1/2" to middle of flat band. You might have been too rich as you are somewhat higher in elevation than me so your air will be thinner & you'll need to be leaner on the needle. Once you get her going then try the X465.

 

[shoboat]

Hey Kevin,

I think a 260 is a little big for a scale at 2000',try something in the 57mm

range. What prop did you have on the A-hydro? It sounds too big also,you

should have excellent throttle response on a 21 rigger. Carb could be a

little on the big side also if you are having trouble. Trying to help you out.

Thanks,

Mark Sholund

 

[Kevin_R_Clark]

Boy getting old, did have the smaller of the 2 on. Will let you know on the next trip, going to the bigger pond and will be much more comfortable.

 

[Scott Schneider]

<_< Just as fast at 1/2 throttle as it is a full? and poor throtleablity? ~~ sounds like too short a pipe for that nitro content and prop load.

Those p-5 piccos are pretty heavy breathers and like the newer mac 21's will be somewhat sloppy sounding on the bench but clean up and run like hell once under load.

.21's also are very very pipe sensitive and will run really well on only the "right" pipe once found. My Picco P-5 EXR's worked the best using the Nova Rossi nitro pipe at @ 8 1/2" to 8 1/4" lenth measuring from the plug around center line of header to weld seam.

Loads of torque? in a .21 ? ~~~~~~ NEVER !

PS. I allways ran them on 40 or 45% fuel with head squish at @ .012 and used the smaller props and let the little engines screem upward of 28 to 30K.

Work with it, you will find the right combo !! if it was easy getting .21's to run fast and consistant out of the box? every one in the .21 class's would be fast and consistant. ~~ It's a really tough class . Scott

 

[Scott Schneider]

And Kevin, If your old engine has a carb that idles and is more stable swap out to the newer engines.

Also as you get into bigger carbs that give great top end you will have lower speed issues that will drive you nuts !! Either back off on props area / raise the strut a tad to unload engine more.

Or raise the compression slighty and keep a richer needle so you won't smoke plugs.

I typically takes me a dozen trips testing with props and pipes and compression adjustments to get most .21's up and running hard and consistantly.

Also found the P-5's to be better mono engines than hydro. Scott

 

[Kevin_R_Clark]

I have been running the boat with a 1250 on it. It was fast, fast, fast with the stock P5. It just seems funny that I was having to lenghten the pipe considering a modded motor and higher nitro content. If I tweaked the needle it would run just as fast as the stock motor but at half throttle. Never did burn a plug. Although it was definetly lean to get this. Now I will say that the stock motor would behave the same way if I got the pipe to short. I am talking moving the pipe in the 1/8 in increments. I am becoming convinced that I was running on the edge before and there is something a little off in my set up. I have a CMB Black quite pipe and an A/B 21s Pipe that I am going to try. The guy who built the boat also sent along a modded 230 prop that he keeps telling me to try and an H-2. This is a very narrow small one of a kind boat that weighs 3- 14. All natural wood made from first growth cedar. Most excellent crafmanship all homemeade harware. Anyhow I do realize 21 Hydro`s are a PIA but i have patience. Thanx Kevin

 

[shoboat]

Hey Kevin,

Try stepping down your propeller diameter a little. We have found 43mm

to 45mm to be the best range to operate in effectively. A 1250 is a little

on the small side for pitch 60mm. Try an H-4 or a H-10 and you will have

a ROCKET 21 RIGGER.

Thanks,

Mark Sholund

 

[Kevin_R_Clark]

Scott,

Yep the old carb had some work done to it. I believe the low speed was taken out and the spray bar was changed. Can`t remember exactly what I was told but do know that it was a modded carb. Anyhow the old motor and carb are up in Canada right now getting a makeover. How about that OS carb I got from you. I read where they are great carbs. Thanx Again for your help, Kevin

 

[Geraghty]

 

[Kevin_R_Clark]

Don,

You will get a chuckle out of this observation, as it is my first big-block. But Holy Smokes Batman does it suck down the fuel. Now I know why you mix your own. I might have to rename the boat Budget Buster, LOL.

 

[Don Ferrette]

Don,You will get a chuckle out of this observation, as it is my first big-block. But Holy Smokes Batman does it suck down the fuel. Now I know why you mix your own. I might have to rename the boat Budget Buster, LOL.

Yup, they sure do. With the mods Sir Orlic put on that motor she runs sweet, but a thirsty little devil.........