Is premium fule neccessary?

Mine runs fine on 87 octane. What does the owner's manual say? If an engine is not designed to take advantage of higher octane, it will not help anything (may even reduce power to run on higher) and, that I know of, these small engines are all built to run run on regular.
 
I doubt if u would notice any difference in performance between the lowest & highest octane levels....not enough anyway to justify the price increase.
 
Most small utility engines are designed to tolerate crappy fuel. They have (relatively) low compression and tame ignition timing. This allows them to run properly on fuel that has degraded quite a bit from storage.

This also allows quite a bit of performance gain if you raise compression ratios and advance the ignition timing. (Briggs, Tecumseh and Honda kart engines are a good example)
 
Most small utility engines are designed to tolerate crappy fuel. They have (relatively) low compression and tame ignition timing. This allows them to run properly on fuel that has degraded quite a bit from storage.

This also allows quite a bit of performance gain if you raise compression ratios and advance the ignition timing. (Briggs, Tecumseh and Honda kart engines are a good example)

Sounds interesting. How do you raise compression and advance the timing on a Honda GXH or Huangsheng copy? Are there drawbacks?
 
If its a true cart engine then were talking apples and oranges here, cart engines cost in the thousands of $$$$ and are not weedwhacker motors.
 
I was thinking of those lil formula cars that go like a bat out of **** around the race tracks.
 
Well, a Honda GXH50 ain't a weed wacker motor- generator, perhaps.

To advance timing would take an offset flywheel key and to raise compression would either require a new, taller piston (not likely to find), or you need to machine the head.
 
Back
Top