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Competition Marine Designs, Inc.
Ph: (386)330-2420
andybrownprops
@gmail.com




CMDi Solid Billet Headers
New Headers from Andy Brown Performance. Solid billet headers are now available. They are available in 10 or 15 degrees.

.21 @ $26.50 .67 or .84 @ $32.50
.45 @ $29.50 .90 @ $34.00


AB 15N
New Billet AB15 Nitro pipe is designed for .12 & .15 engines and also works great on .18 RTR engines. This pipe is best suited for Hydros and Riggers. Only $39.95


Brown 21 Fat Pipe
We are proud to present the newest 21 pipe in our line up; the Brown 21 FAT pipe. This pipe has been designed by Andy using all of his vast experience to develop a pipe which is able to produce more overall midrange and top end power with no sacrifice in launch ability and bottom end transition for most engine and hull combinations. Initial tests are proving that out of corner acceleration is more explosive and top end is increased with no other changes to boat, prop, or engine.


Brown 21 Parabolic-
Great all around pipe for Mono's and Hyrdo's
NAMBA Sport 21 Hydro racing record holder (Jim Wilson).

Works with MAC 21 14 mm headers. (large O.D.)
Recommended pipe length 7.8" to 8.3" (cylinder center to weld).


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Brown 21 S-
A small volume version of the Brown 21 Parabolic pipe. This new pipe will produce more top end rpm with little or no loss of low end torque. This pipe also has the rear cone moved closer to the engine which will allow shorter settings when used on engines that utilize a 180 degree header.
Recommended pipe length 7.8" to 8.3" (cylinder center to weld).


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Brown 21 Long-
This is the newest updated version with less restrictive stinger. The 21 Long pipe has divergent and convergent cones that are very similar to the ever popular OPS 21 pipe. This is a great all around pipe for all .21 hull and engine combinations. Best length is 8.0" to 8.5" from center of cylinder to weld seam on pipe.





AB 21SS
The AB 21SS pipe is designed to achieve high rpm from .21 engines that use 180 degree headers, while at the same time producing good throttle response for racing. The header section of the AB 21SS pipe will telescope over standard Novarossi, Picco, CMB 180 degree headers. Many other pipes are too long or have too much volume to get maximum rpm from engines utilizing 180 headers. The AB 21SS pipe is available with standard muffler or with extra muffling.





AB 21ST
The AB 21ST pipe is designed to achieve high rpm from .21 engines that use a 180 degree headers, while at the same time producing good throttle response for racing. Additionally, the AB 21ST will produce more torque in the mid range to top rpm for those who like to pull big props or have slightly more hull drag.

The header section of the AB 21ST pipe will telescope over standard Novarossi, Picco, CMB 180 degree headers. Many other pipes are too long or have too much volume to get maximum rpm from engines utilizing 180 headers. The AB 21ST pipe is available with standard muffler or with extra muffling.





AB 21STL
The AB21STL is long version of the AB21ST for use with the rear exhaust .21 engines.




AB 21RX Nitro
Nitro pipe is a great torque pipe for oval racing with .21 outriggers.






AB 21XT
The AB 21 XT pipe is designed for good broad range power for the MAC 21 engine. The AB 21 XT telescopes of the 14mm MAC tapered header. The AB 21 XT is a smaller diameter than the AB 21 FAT pipe yet will have nearly the same performance characteristics. The AB 21 XT pipe is available with standard muffler or with extra muffling.






AB 45 XTS
The AB 45 XTS is a short belly version of the AB 45 XT. This pipe is well suited for Picco, CMB, O.S.Max, and OPS 45 engines. The AB XTS will work on light SAW set-ups on the MAC 45 or when utilized with a special long header for the MAC 45. The AB 21 XTS pipe is available with standard muffler or with extra muffling.




Brown 45 Parabolic-
The Hottest 45 pipe available today. Well suited for all 45 sized engines and all hull types.
IMPBA "D" Hydro SAW (Andy Brown) and OVAL (John Brown) record holder.
2002 National and World Champion.

Works best with MAC 45 tapered header.
Recommended pipe length 9.5" (cylinder center to weld).





New AB 45XT pipes
The new AB 45XT pipe has been developed to provide extra off the corner acceleration while maintaining top end rev out for peak speed. Compared to the Brown 45 parabolic pipe the same off the corner acceleration will be noticed while an increased top end will be realized. The new AB 45XT is suitable for a wide range of hulls and will offer great performance for sport hydros, vees and cats when used at the longer length. For light weight riggers the XT will produce a very wide powerband at a shorter length.

The AB 45XT is available with standard muffling or with Extra muffling.



Brown 67 Parabolic-
This pipe is working well in many applications.
Has many Major race wins and Records including,
IMPBA "E" and "F" SAW (Andy Brown) and 1/8 scale Unlimited SAW and OVAL (Gary Preusse)
First pipe to exceed 126 mph in an R/C Boat.
NAMBA C Hydro (Roger Hooks, Jr.)
For racing this pipe has very good broad range power.
23 -25cc Gas engines are working well with this pipe. (requires Hanson type header)
Our 25cc Zenoah powered SGX rigger consistantly at 78 mph with this pipe.
Recommended pipe length for .67 to .84 Nitro is 11.0" (cylinder center to weld).




AB 67-
This is our newest addition to the line of Andy Brown performance pipes and early testing is showing that this may be the best .67 pipe ever.
The AB 67 pipe was designed for a wide range of applications.
The AB 67 pipe provides very good torque for slow milling coupled with great top end RPM's.
.67 and .84 engines will benefit from this pipe as well as some .90's.
We have developed a new tapered I.D. header to make this pipe a perfect match to the MAC 67 exhaust outlet. (17 mm I.D.)
For other .67's, .80's and the MAC 84 use the standard 18 mm I.D. header.
The AB 67 pipe will telescope over the header ( may require reducing the O.D. of the header slightly ).
Recommended pipe lenghth - 10.8" ( cylinder center to weld )


AB 67 Bushings-
We now have available stinger bushing sets for the AB 67 pipe. The purpose of these bushings is to fine-tune the pipe backpressure according to the needs of a particular engine and weather conditions. The AB 67 has a Stinger I.D. of .470”. This size is good for most .80 - .84 engines and some .67 engines in very hot weather conditions. For most .67 engines and cooler weather conditions a smaller stinger I.D. will provide better performance. Our early testing with this system has shown that a .410” stinger I.D. works well on the MAC 67 in cool weather. A stinger I.D. of .450” and .470” both work well for the MAC 84 in cool weather. Hot weather normally requires a slightly larger I.D.

These stinger bushings are available in sets of three sizes ( .410”, .430”, .450” ) or individually.




New improved bar stock AB67 pipes
The new Billet AB 67-80 pipe is machined from solid barstock. This new design was used by Henry Velasko at the 2007 NAMBA Nationals to help him set the Fast Time and become the C Hydro National Champion.

This pipe is available with Standard muffling and Extra muffling.



Brown 84 Parabolic-
This pipe produces very good RPM's for .80 to .84 engines.
Works great on .67 to .84 engines in mono hulls and is well suited for the .80 to .84 engines in Hydros.
Holds the NAMBA "C" and "X"mono SAW records along with the "X" mono 1 mile heat racing record.(Erik McNair) and has many major race wins.
This pipe is also great on 23 - 25 cc Gas engines. (requires Hanson type header)
Recommended pipe length - 11.5" to 12" ( cyliner center to weld )




New bar stock AB90-100 pipes
This is the first ever 90-100 pipe offering from Andy Brown Performance. Machined for solid barstock, this pipe is available with Standard or Extra muffling.

A machined tapered header will soon will soon be available for a perfect match to CMB 90-101 engines.

Parts & Price List:
CLICK HERE to open our price list for the Andy Brown High Performance Tuned Pipes, and components. To view our price list, you must have Adobe Acrobat PDF Reader installed on your computer system. If you do not have it installed, CLICK HERE to download it FREE.