Download SeaDoo SP Technical data

Section 04 ENGINE
Sub-Section 02 (TOP END)
Item P1 in figure is the pressure of the return
spring against the diaphragm. The exhaust pressure must be high enough to overcome this pressure before the valve begins opening. Item P2 is
the pressure required to completely open the
RAVE valve. Between P1 and P2, the usable power curve of the engine is moving from power
curve 1 to power curve 2. This transition takes
place very rapidly at full throttle and from a practical standpoint can be considered to be instantaneous at item 7. Gradual application of the
throttle, however, will result in the RAVE valve
opening much later.
If the RAVE valve opens too late, the engine will
bog or hesitate momentarily as the RPM increases. Full peak performance (item 6) is still available.
From a functional point of view. It is better to have
the valve open a bit early than a bit late.
F01D7GA
VALVE FULLY OPENED
P1
P2
7
6
1
POWER
F01D7HA
VALVE FULLY CLOSED
1
The RAVE valve does not allow an engine to make
higher peak horsepower than an engine not so
equipped, it can make moving the peak higher
practical because of its effect on the rest of the
power curve. Item 2 in the following figure is the
power curve of an engine with the RAVE valve
held fully open through its entire RPM range. Item
6 notes the peak power produced. That peak will
not change if the exhaust port time of a similar
engine without a RAVE valve was the same (with
all other features equal).
Item 1 is the power curve of the engine with the
RAVE valve closed through its entire RPM range.
The shaded area (item 3) is the improvement in
power at lower engine speeds that is gained because of the lower exhaust port. If the port remains at this height, however, the power would
peak as noted in item 5. Raising the exhaust port
at the proper RPM (item 7) will allow the engine
peak power to continue to rise (item 6).
5
3
A18C02A
4
2
RPM
Maintenance
There are no wear parts anywhere in the system
and there are no adjustments to be periodically
checked. The only possible maintenance required
would be cleaning of carbon deposits from the
guillotine slide. Cleaning intervals would depend
upon the user’s riding style and the quality of the
oil used. Using FORMULA XP-S synthetic injection oil, we would suggest annual cleaning of the
valve. If a customer uses a lower quality oil, more
frequent cleaning may be required.
No special solvents or cleaners are required when
cleaning the valve.
040-02-16
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