Tuned pipe setup

[Bryan calabrese]

I was speaking to a newbie at my pond last week and he asked me about tuned pipe lengths and I really didn't have a answer for him since engine size pipe type and hull have alot to do with it I told him to check out intlwaters he got back to me and he said couldn't find anything . So does anyone want to throw there two cents in on maybe were to start to get to the proper tuned pipe setup .thanks

 

[Danny King]

A good place to start is with more info…
Engine size
Boat type
Performance goal
Nitro content

 

[Bryan calabrese]

My bad he has a 1/8th scale hydro with a cmb 67 he is running 40 percent as the brand pipe I believe it's a large volume cmb tuned pipe

 

[Wasted wages]

large heavy hull, lots of hull drag until fully on plane....

Scales usually need:
A smaller prop & longer pipe, say 12" -12.5" or so to start.

Get the boat up and planing first, so it will pull away from the dock properly and mill the course... once it makes consistent laps, then start shortening the pipe 1/4" at a time until it falls off the pipe... then pull it back out to the last length it ran good. Record the length for future reference.

Motor needs to be in good shape, good bearings, head clearance set, good pinch on the sleeve, tight carb, rotor clearance set. good fuel tank and lines, no air leaks..

 

[Danny King]

11.25” is a common length on that pipe. But not on a unproven scale.
12” would be a good place to start.
start long and get it making laps. It will be more fun amd easier on plugs with a long pipe.

 

[Wasted wages]

What model CMB .67 is it ??
I used to run a cmb quiet pipe on an older cmb and it pulled really good...
Also ran a Mac quiet pipe that worked good too.
Longer pipe =torque
Shorter pipe =RPM

A few pictures of the hull and motor setup along with current pipe setup and length and current prop size will help..

 

[Bryan calabrese]

What model CMB .67 is it ??
I used to run a cmb quiet pipe on an older cmb and it pulled really good...
Also ran a Mac quiet pipe that worked good too.new 67 hr

What model CMB .67 is it ??
I used to run a cmb quiet pipe on an older cmb and it pulled really good...
Also ran a Mac quiet pipe that worked good too.
Longer pipe =torque
Shorter pipe =RPM

A few pictures of the hull and motor setup along with current pipe setup and length and current prop size will help..

It's a new 67 hr
Longer pipe =torque
Shorter pipe =RPM

A few pictures of the hull and motor setup along with current pipe setup and length and current prop size will help..