67 cmb pipe length

[PHM Racing]

what are you guy's setting your pipe length at i have a 67 cmb green head with the cmb fat belly nitro pipe with a stinger what do you guy's think the best length for this pipe is and i have a 67 mac pipe whats a good pipe length for that and i have one more pipe it is a 67 irwin quiet pipe i was told that if you drill five 1/8 hole's in the end of the pipe it will work better has anybody tried this.

Any info is good in info.

Thankx Mike

 

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I started my pipe length at 12 inches and finished at 11 3/4.

As for drilling the holes I've haven't tried that myself. A guy named Jim Williamson years back gave me a pipe like that for free, didn't really notice any difference though.

 

[mike]

pipe length on 67 greenhead & bigbelly pipe in my rigger is 11 inches pulling 1467 octura worked, radars 73 + with this setup, boat weighs a bit over 7 1/2 pounds.

 

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Mike,

what type of rigger is that in? How do you like those 1467 props??

 

[mike]

Rod,

The rigger is built by a guy here locally, kind of resembles a roadrunner but it has differences, the 1467 is ok with a bit of bending have a 1667 to try this season if the wind ever dies down ha!! The boat recovers quickly out of a turn, so think I need more prop ha!! also the pipe length is 11 inches, sure makes that baby wind up...........

 

[aaron alberico]

i run a small cmb pipe at 11 1/2, or i run the big belly cmb pipe at 9 1/2 on my green head cmb in a eagle sg rigger with a mod h667 running bout 90mph+

 

[jeff baham]

guys can you tell me and others how you are getting your lengths on your pipes ,from the plug to what part of the pipe. i run my gold head cmb 67 with the big belly pipe 10'' from the plug to the start of the flat stop on pipe. this is also in a rigger, my design HORNET HYDROS.

 

[jeff baham]

guys can you tell me and others how you are getting your lengths on your pipes ,from the plug to what part of the pipe. i run my gold head cmb 67 with the big belly pipe, 10'' from the plug to the start of the flat stop on pipe. this is also in a rigger, my design HORNET HYDROS.

 

[jeff baham]

SORRY FOR THE DOUBLE POST, HOW CAN I REMOVE ONE OF THEM.

 

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I stole my wife's soft tape measure she uses for sewing. I put a small hole in the piece of metal in the beginning of it that keeps the tape from fraying, this way I put the tip of the glow plug through it and can just pull it with one hand. To get my measurments I start from the tip of the glo-plug to the fat part of the pipe.

On motors that have headers in the front I start at the plug and roll it around the header up to the fat part of the pipe.

 

[PHM Racing]

Thanks guys i guess there alot of variables to pipe length like hull weight ,length,design ,prop.

I run one of my own Screaming Eagle rigger's it weigh's 6 1/2 pounds ready to go and i'm using a 1465 prop right know i have the pipe at 11 3/4 from the plug to the weld not to the start of the flat should i be measuring to the start of the flat .

I see some are set at 9" and 10"

Mike

 

[TimD]

Mike,

With the big belly pipe - if it starts to sound like it is going rich towards the ends of the straights, you can drill 2 x 1/8" holes just before the stinger and it seems to stop that problem. I had this with a picco.

Tim.