We have done extensive testing on pipes for .108 - .140 size engines. In fact we have had these pipes in production and testing a full year before the new rules came into operation. In our testing we have found several engines that do not respond as they should to a pipe, mainly due to an exhaust timing that is too low. The normal pipe system should improve rpm by 600 - 800 rpm over open exhaust, but for engines with insufficient exhaust timing (less than 142 - 145 degrees), the rpm increase is insignificant, and the engine will not respond correctly to the throttle, often going rich in mid range.

The below range is made of a Carbon / Kevlar mix. We know of no better pipes for strength to weight, performance, low noise or broad operating range.

EQ 2000 This is our well established basic pipe for .108 to .120.

EQ 2002-N Our standard .120 / .140 pipe.

EQ 2003-S The square version of the 2002, very smooth performance.

EQ 2004-L This is the Long taper version of the 2002, slightly less power but very broad range.

An engine test / review of the Webra 120, 2 stroke engine by Mike Billington, which appeared in Model Airplane News, October 1994, (and an English publication of a similar time), shows the EQ 2000 pipe to be of exceptionally good performance, especially in regard to torque. This test (the only one of it’s type that we know of to include a Bolly EQ pipe), was done at a 650mm operating length, resulting in a maximum torque at 7,490 rpm. Another test at a 680mm length resulted in 6,900 rpm using a Bolly 18 x 10, 3 blade prop. This is an excellent test to read as it displays the torque and power characteristics of the Bolly EQ pipes.

These pipes are used at between 590 to 650 mm operating length, for rpm between 8,800 to 7,800.

We believe Bolly has the worlds best .60 size F3A pipe, in the EQ 63, the great pity for us is that is was developed too late to become appreciated by the modellers, as the world was turning to the 4 strokes.

EQ 60 This is our standard pipe. As good as almost all metal pipes with the advantages of lower weight. A very smooth performer.

EQ 62 A larger diameter and slightly longer version of the EQ 60. Smooth and quiet with better power. This is our most popular pipe.

EQ 62N This is our latest pipe. Basically a rectangular version of the EQ 62 / 63. We believe this is our best pipe for a power / size compromise.

EQ 63 A very unique pipe, square in shape, with awesome power. Noise at the same rpm is the same as the above pipes. This pipe is usually 300 - 500 rpm better than the EQ60, with the other sizes between these.

These pipes are usually used at a length between 490mm (10,500 rpm) to 540mm (9,500 rpm).

Used extensively by Quique Somenzini, with whom we do a lot of development work. These are tuned length, slight power gain pipes. They can be used shorter if required for a minimal power loss. The biggest advantage of these pipes is the excellent low noise sound.

As 4 strokes run much hotter it must be stressed that these pipes MUST be well cooled. Pipe attachment needs to be given careful consideration as the exhaust gas can melt silicon connectors. The longer the header the better. Where possible use a metal fitting to sleeve over (and inside) the pipe and header.

FS 120 Somenzini Our second generation of 4 stroke pipes, long and thin.

FS 120 Somenzini Narrow A rectangular version of the above.

Please Note: The above 2 pipes have been discontinued (replaced by the FS-122 / FS-124

FS 122 Somenzini Our 3rd generation of 4 stroke pipe. This is a much more compact but larger volume version of the FS120 versions. Rectangular in shape.

FS 123 A 4 chamber version of the FS122, DISCONTINUED (too heavy)

FS 124 (Somenzini) As per the FS 122, but featuring an aviation grade alloy header tube, as an integral part of the pipe. Combined with our improved pipe resin, and carbon / kevlar makes for a pipe far more capable of withstanding 4 stoke exhaust temperatures than previous versions. The volume of this pipe makes it very suitable for the larger size 4 strokes that will soon be available under the new 1996 F3A rules.

FS 90 Designed for the new YS 90AC or similar engine.

FS After Muffler Designed to plug onto the end of the FS122 / 124, or to be used separately as a ‘sports’ 4 stroke muffler.

Most large scale models (over 30cc), use petrol engines. This introduces a problem for exhaust systems (metal or carbon) due to the extra heat these engines develop. It is vital that careful consideration be given to cooling on these models, which generally use a fully enclosed exhaust system.

The best method we have found is to use a long alloy header to dissipate the heat before it gets to the pipe or muffler (metal or composite). The heat of these engines also makes it difficult to build headers that survive this operating environment.

Note: Vibration levels of these engines (especially the larger single cylinder versions), can be very high, and posed as many problems as the heat. We advise the modeller think very carefully about using pipes (metal or composite) on larger (above 50cc) engines, as the problems are many.

Bearing the above in mind we have a good range of products for the large model. The EQ range all operate similar to pattern quiet pipes.

The EQ7000 Has been designed for the 60 to 80 cc engines.

EQ-Zehoah62 Has been designed in conjunction with the Zenoah G-62, Australia’s most popular large engine. Will suit any engine 45 to 65cc. Uses our latest square pipe technology. This pipe has a large (id) header section to sleeve over the allow header. This reduces the need for a silicon joiner, which are prone to burning out on engines of this size.

EQ5000 For engines 35 to 55cc. The test engine was a Sachs 3.2.

EQ3002 A very popular pipe on 25 to 35cc engines (e.g. Moki 180 or Super Tigre 3000 / 3250 ).

TOC Somenzini Developed for use on 3W60 twins, (2 pipes @ 30cc each side), for use in the Las Vegas TOC event. More powerful and more noise than the equivalent EQ pipe. Suitable for 30 to 40cc use.

EQ2002 / 2003 / 2004 Excellent pipes, see previous pattern section.

EQ2000 For engines 15 to 20cc.

Don’t forget the range of After or Super mufflers. The Super Mufflers are especially handy where space or cost prevents the use of a full length pipe.

The Bolly P21 has proven to be very popular for Australian Quarter Midget rules (using .21 engines). For some years it has been the most popular and successful pipe in Australian QM racing, especially the short version, when combined with the Rossi 21.

For FAI use we have the P42, designed in collaboration with the Bruce DeChastel who had a hand in the world’s most popular alloy pipe for pylon, the ‘MACS’ pipe. The most recent P42 have a larger 7.2mm diameter stinger which performs much better than the older 6.4mm stinger. Some customers are reporting a 8mm stinger is better again.

We are working on a new design, which when released will be the P43 (stands for P40, type 3). (July 96, at present this development is on hold until 1997)

The FAI pipes are available with different headers and bent stinger as an option.

We have done extensive development of our ducted fan pipes, in particular the QP90. This pipe is light, powerful and quiet. It is slightly larger in volume than most and benefits from being used in an ‘area rule’ tail pipe which allows for the pipe volume..... this makes for an unbeatable combination.

Note: The QP90 has now been replaced by the DF-91B. The DF-91B has been designed to withstand higher levels of vibration then the old QP90, otherwise the performance is very similar.

Our old P90 is a very noisy pipe now outperformed by the QP90, however we have developed the new P92 which is more powerful and easier to use, but noisy. Great for where power is more important than noise, i.e. setting speed records etc. Please note the ‘P’ pipes are not as easy to use as the QP / DF style.

The P90 is well suited to old .65 to .77 engines.

The .45 size ducted fan models are well served by the P45 and QP45 pipes.

More often the sports flyer is turning to pipes for quietness and discovering the power benefits. The ‘sports’ modeller is not as restrained by rules or scale appearance making the fitting of a pipe very easy.

Many a ‘Hots’ style model is flying with a pipe. All Bolly pipes are suitable for this type of application.

Don’t forget the range of After or Super mufflers. The Super Mufflers are especially handy where space or cost prevents the use of a full length pipe.

Finding the correct pipe for helicopter use is difficult, as few pipes have the ability to produce good power and be broad range enough to be ‘on the pipe’ properly at hover and top speed. Often a compromise must be found that suits top end performance at the expense of a rich hover, or a great hover at the expense of absolute top end power.

Use the EQ pipes at 450mm length for ‘hover’, or 430mm for ‘top end’ performance.

Also troublesome is a good header to arrange for a pipe to be positioned parallel with the boom.

Full length pipes (c/f or alloy) should not be used with full body choppers due to inadequate cooling arrangements usually found in this environment.

The EQ30 has proven to be an absolutely wonderful pipe on the .30 size helicopters (.28 to .34), when used at an operating length of 430mm. Ask for the EQ30H version.

The main area of pipe use for control line is aerobatics where our range of EQ30 , 45 and 60 are quite suitable. These pipes are a larger volume than some of the more popular pipes, and as such are less critical to set-up and use. They are also quieter than many other types.

The C/L Speed classes also use pipes, for which our Power pipe range is suitable. The P15 was developed in conjunction with the late Ivars Dislers, where it showed great promise, cooling being a problem in the airframes set-up for smaller alloy pipes.