Salisbury
Power pipes
EQ 3002
Designed for 28cc through to 35cc 2 stroke engines. Best for 7,000 to
8,500rpm
EQ 2000
Designed for 18cc through to 24cc 2 stroke
engines. Best for 8,500 to 10,000rpm.
The EQ-3002 and EQ-2000 are related to our very popular range of EQ (Extra Quiet) pipes for pattern engines, for sports engines operating at ‘normal’ rpm. These pipes are very broad range with high torque characteristics and can cope with most situations, but for lower rpm’s, we would recommend the EQ-120R, EQ-140R or EQ180R.
All Salisbury EQ Series Pipes have an optimum 'operating length'. This length is quoted as a distance in mm from the exhaust (piston face) via any curves in the alloy header pipe to the first baffle inside the pipe. The system's length is varied by shortening the header (preferred as it is heavier than the C/F), or lengthened by adding a spacer to the system... usually by inserting a length of header cut-off, inside a longer piece of silicon (available from Bolly Products).
To find the pipe's first baffle, insert a rod inside the pipe until it contacts the baffle. Mark it's position on the outside of the pipe. .... Caution.... the first baffle has a hole in the centre, double check that you haven't found the second baffle.
This
pipe / muffler should be rubber mounted at or near it’s C of G. Excessive heat
and vibration are the biggest destroyers of exhaust systems (metal or
composite).We use the Bolly 'Tuned Pipe Mount' combined with a Bolly Iso-Mount
& a cable tie for the rearward attachment.
These pipes will work at any reasonable length, however only trial and error will find the best combination of pipe length, prop size, head clearance and fuel etc. Below are the recommended lengths from our development testing. Use only as a guide as there are literally thousands of possible combinations.
30 - 33cc
EQ 3002 @ 680mm - Bolly 20 x 10 or 18 x 10 3B
7,500 rpm
28 - 30cc
EQ 3002 @ 660mm - Bolly 19 x 10 or 16.5 x 10 3B
8,000 rpm
20 – 24cc
EQ 2000 @ 615mm - Bolly 17 x 10
or 16.5 x 12
8,500 rpm
18 – 20cc
EQ 2000 @ 545mm - Bolly 16.5 x 8
or 16 x 10
9,500rpm
Please note: the above is only a guide and is subject to a large variation depending on the overall setup.
Low rpm = longer pipe ; Higher rpm = shorter pipe. When in doubt, use the pipe long. It is a safer option than being too short.
Pipe too short: = frequent blowing of plugs Pipe too long: = prone to burbling rich running
= overheating engine = low power, low noise levels
= sags under load - ie in climbs
= harsh and /
or lean running despite taking off with a good needle setting.
Please note: The symptoms of being too short may also occur if the
engine is over compressed (often the case when using a pipe on an engine not
specifically designed for pipe use) ..... Using a pipe will increase the
effective compression ratio of an engine. (as will adding more nitro to the
fuel). Add a .1 to .2mm shim under the head
to decrease the compression.
Beware: We have found
that some of the larger 2 stoke engines have very low exhaust timing (below 145
degrees), and do not respond as they should on a pipe. If the engine is too low
on exhaust timing, the pipe may cause poor throttle response or even inhibit the
engine performance. Such engines will usually go rich with throttle transition
from idle to full power. In these cases, use a very long pipe (it will now act
like a muffler) and a hot plug.
Caution: Petrol / spark ignition engines run much hotter than methanol versions. Engine, header and pipe cooling are very important. The silicon joiner provided will suffer if a petrol – spark engine is run hot (ie too lean) or when stressed (bent). Large single cylinder engines are often suffer severe vibration, hence careful pipe and engine mounting is paramount.