MVVS 30 IFS User Manual
Page 4

Exhaust
 
Use only factory-made exhausts pipes designed for this type of engine, preferably brand-name MVVS 
engines with which you also get the power output guaranteed. 
The manufacturer declines all responsibility for all engine damages arising from the use of improper 
exhaust systems. 
When mounting the exhaust follow the manufacturer’s instructions. Make sure to secure sufficient cooling 
of the exhaust. 
 
3270 
compact, medium level of power output
3266
tuned pipe, with adaptor 3265 provides the highest power output, with the flat torque curve, 
useful for the model planes 
 
 
3266 
 
 
3270 3265
 
 
Carburetor adjustment
 
Basic setting: 
adjusting needle ( L ) for low RpM range 1 turn and 40 minutes 
adjusting needle ( H ) for high RpM range 1 turn and 40 minutes 
for WT 561
Minutes refer to hands of a clock. Values are only approximate and may vary with size of the propeller. 
 
Walbro WT 561
The new engine comes adjusted to the basic setting. 
After the engine has been run in, adjust it following the instructions below: 
- start the engine and warm it up 
- let the engine run at idle speed for approx. 5 seconds 
 
Step I 
Accelerate to 2/3 of the throttle range within approx. 1 sec (faster acceleration). Repeat three
times – if the engine accelerates quickly and without a hiccup go to Step III. If acceleration is not smooth 
go on to Step II. 
 
Choke
H- needle adjusting 
screw 
L- needle adjusting screw
Lever - throttle
Pressure pulse inlet
