Pipe length

[Blake johnson]

I have a cmb 90 and a Mac pipe. What length should it be cut at?

Blake

 

[Ray Sametz]

On my CMB gold head, I ran at 12 inches. B)

 

[julianconde]

11 1/2 to 12 is a good number depends on what you wanna do.

julian

 

[John Knight]

Depends on what hull is being used. However, 12" is a very good number to start with. It is what I have my CMB 90 and MACS pipe at now on a rigger.

 

[ALLAN YUEN]

I have a cmb 90 and a Mac pipe. What length should it be cut at?

Blake

Depend on what kind of boat? CMB90s Gold head w/ MAC big belly 1" pipe 12" fastest for my Twin rigger. I never cut at pipe or header so I punch flare on pipe and connect( tapped) header I.D and pipe O.D Reason can play adjust +/- 3/4" more safe because trip different place state..If you cut header or pipe so the coupler will blow out hole or burn melt also lot of replace new couplers Good Luck!

 

[Blake johnson]

I have it in a sightler 50" rail. Right now the pipe is 16" long and the header is 3" long.

 

[ALLAN YUEN]

I have it in a sightler 50" rail. Right now the pipe is 16" long and the header is 3" long.

better start 13" will play adjust down 1/4" more aprox about 1 inch run with your mono Good Luck!

 

[Blake johnson]

If I put it at 13" it looks like the pipe wouldn't fit in the coupler anymore.

 

[Ray Sametz]

I have it in a sightler 50" rail. Right now the pipe is 16" long and the header is 3" long.

16 inches, measured from where to where? If you have too, shorten the header. 12 inches is center of cylinder to start of pipe belly. B)

 

[julianconde]

i have to agree with HAMMER 16 is way to long and never cut the pipe just shorten the header..

julian

 

[Blake johnson]

My bad. The pipe it self is 16 inches long and the header is 3" long.If I measure from the center of the cylinder to the very end if the pipe including header it is 20" long . When i I measured from the center of the cylinder to the start of the pipe belly it is 13 3/4" long

 

[dwilfong]

Pipe length depend on many things. load on the eng and of course how much nitro you run. when you shorten the pipe the RPM potential of the eng increases. the pipe is the governor on the eng. if the power of the eng can not run the prop at the RPM you have set by the pipe length. it will not come on pipe.With higher nitro you will make more power making it easer to shorten the pipe with a bigger prop.

On a CMB 90 with a 13cc MACS pipe 12 1/2" from center of the cly to the center of the pipe where the front and back cones meet will get you started with most any set up.

When you can bring it down to 11' you have it on the money.

You will have to cut the header and the pipe. Get the MACS 1384 1" lead in pipe then it will slide over the header.

David