Saito make some engines that are fueled by gasoline(petrol) with spark ignition.
These are essentially the same engines as the glow-fuel versions but with the addition
of a spark plug, electronic ignition, and different carb.
The glow fueled engines are designated FA-  and the gasoline fueled engines as FG-
For example the FG-36  and  FA-220  are gasoline and glow engines of identical physical size and capacity. The ‘36’ number refers to the capacity in cubic centimeters. The number ‘220’ refers to the capacity in cubic inches x10, viz 220 means 2.2 cubic inches capacity. For some unknown reason Saito has chosen the different units to describe the capacities for gas and glow versions of their engines.
 

The available gasoline/petrol engines are:
FG-36    (glow version FA-220)
FG-30    (glow version FA-180)
FG-20    (glow version FA-125a)
FG-14    (glow version FA-82a)

FUEL:  Gasoline (Petrol) needs to be mixed with oil in the ratio 20:1
              There are 128 fluid ounces in a US gallon, therefore 6.4 ounces of oil needs to be added to
              each gallon to get the correct oil content.
              The imperial-size gallon has 160 fluid ounces and therefore 8.0 fluid ounces of oil
              would need to be added to one imperial-size gallon.

The Walbro pump-type carb on the FG-36 and FG-30 engines permits the fuel tank to be located relatively distant from the engine, and the tank height with respect to the carb is not critical. By comparison, the glow engines work best when the tank mid-point is about level (or a little lower) with the carb, and the tank is close behind the engine. Muffler pressure is not necessary, and not used with these FG engines.
The smaller FG-14 and FG-20 use a Saito-designed carb. For these engines the tank is best placed near the engine similar to the usual  practice for glow-fueled engines.

There is additional weight to be carried compared to a glow-fuel engine. The ignition unit and a 4 or 5 cell  NiCad or NiMH battery of 1000mAH or larger is necessary. However this extra weight is only a few ounces and is offset by the fact that the engines are very light for their capacities, plus a smaller fuel tank is possible with gasoline due to the significantly lower fuel consumption.

There is a reduction of power compared to glow-fuel, however that is an unavoidable consequence of using gasoline instead of alcohol fuel. Nevertheless the power is quite adequate for most applications and the operating cost for gasoline fuel is significantly less than glow fuel.

IMPORTANT !!
1. Read the instruction manual carefully. Make sure you have the most recent 2009 version of the manual. If you do not have this manual it can be downloaded from the Horizon Hobbies web site.

Correct adjustment of the fuel mixture needles can be challenging and is considerably more difficult than for the glow engines. The manual is most helpful.

2. Make sure you use a good fuel filter such as the Sullivan type. It is most important that no dirt get into the carb.

3. It is best to use the Horizon Hobbies recommended oil,

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