A.B. Parabolic pipe for a Mac .67

[Overboard]

I drilled out 4 of my .45 parabolic pipes and I got more speed. Should i drill out my new .67 parabolic pipe also for my mac .67?

 

[Don Ferrette]

I drilled out 4 of my .45 parabolic pipes and I got more speed. Should i drill out my new .67 parabolic pipe also for my mac .67?

FWIW all my parabolics are drilled out to stinger i.d. For me that's how they work best. You can try working the size up a few steps at a time to see the impact drilling has on your particular application. B)

 

[SayMikey]

I drilled out 4 of my .45 parabolic pipes and I got more speed. Should i drill out my new .67 parabolic pipe also for my mac .67?

FWIW all my parabolics are drilled out to stinger i.d. For me that's how they work best. You can try working the size up a few steps at a time to see the impact drilling has on your particular application. B)

i run a mac67 in a scale an its drilled like Don said. You need to drill it if your running in hot humid weather...Mike

 

[ALLAN YUEN]

I drilled out 4 of my .45 parabolic pipes and I got more speed. Should i drill out my new .67 parabolic pipe also for my mac .67?

FWIW all my parabolics are drilled out to stinger i.d. For me that's how they work best. You can try working the size up a few steps at a time to see the impact drilling has on your particular application. B)

:huh: I never drill on Brown 67( silver) Parabolic because the weather depend hot or cold all working No problem!! I heard that club boat always make complain about only Brown 45 Parabolic also some Brown 21 Parabolic because all time run then quit. I remembered that Andy Brown said can use drill little big hole( doesnt drill over big hole out) inside aluiminin shim tube for only Brown 45 Paraobic and it works improve more speed and better much run. B) Good Luck! Allan

 

[Overboard]

I drilled out 4 of my .45 parabolic pipes and I got more speed. Should i drill out my new .67 parabolic pipe also for my mac .67?

FWIW all my parabolics are drilled out to stinger i.d. For me that's how they work best. You can try working the size up a few steps at a time to see the impact drilling has on your particular application. B)

i run a mac67 in a scale an its drilled like Don said. You need to drill it if your running in hot humid weather...Mike

It does not get humid in northern california but I noticed that My .45 parabolic pipes that I drilled out ran faster summer and winter that the pipe that was not drilled out...Ray

 

[ALLAN YUEN]

h34r: I read web:CMDI that the Brown 67 Parabolic make succeed over 115.2 mph no drill I sold my SG Twin 84s with B 67 Parabolic pipes NO drill to Northern California .It really fast and nothing wrong. If you contact to Andy Brown more information. B)

 

[Duck899]

Drill em' out.......you can always shim the stinger......

Mine are all drilled out.....they came alive after they were drilled out.....this includes the 21 pipes.....

 

[nitro_nemesis]

By drilling out...you guyz are talking about increasing the bore size @ the tail end/front end or both ends of the pipe ??? :unsure:

 

[Don Ferrette]

By drilling out...you guyz are talking about increasing the bore size @ the tail end/front end or both ends of the pipe ??? :unsure:

Mark, there is a baffle plate just before the stinger inside the pipe. The hole in the baffle is significantly smaller than the stinger i.d. There are some people who run the pipes undrilled, some who drill them up in size a little. I think most of us drill the hole in the baffle to the same size as the i.d. of the stinger. All of my parabolics work noticeably better this way from the 21 to the twin. If you drill the baffle just be sure to take extra care to be certain all the drilling fragments are completely out of the pipe (it's easy for them to get hung up inside). B)

 

[nitro_nemesis]

By drilling out...you guyz are talking about increasing the bore size @ the tail end/front end or both ends of the pipe ??? :unsure:

Mark, there is a baffle plate just before the stinger inside the pipe. The hole in the baffle is significantly smaller than the stinger i.d. There are some people who run the pipes undrilled, some who drill them up in size a little. I think most of us drill the hole in the baffle to the same size as the i.d. of the stinger. All of my parabolics work noticeably better this way from the 21 to the twin. If you drill the baffle just be sure to take extra care to be certain all the drilling fragments are completely out of the pipe (it's easy for them to get hung up inside). B)

Gotcha, thanks Don