340 Lfire motor in a 440 sled.. Recommendations?

[deerefanatic]

Hey guys.... In order to get a second lease on this snowmobiling season, I threw a spare 340 Liquifire CCW into my 78 440 L-fire......But, here is my question.

This baby is still geared and clutched as a 440? Other than being a dog off the line, it seems to run ok. BUT, will it hurt anything running this way (other than accelerated belt wear on take-off)

Another thing I noticed is a took it for a real quick spin last night...... The exhaust note seems to be much sharper and more pronounced than my 440 sleds.... They always had a more dull exhaust note... Is this normal or do I need to investigate further? I really, really REALLY don't want to bomb another motor!!

Last thing, I put new crank seals in this 340, and took the carbs that came with it all apart and soaked them in cleaner. Everything is correct jetting-wise except they have 6DH8 needles instead of 6DH3.... Is that a problem?

[harleysportster]

The 440 will work and as you thought, it will be sluggess off the line. Besides the chaincase gearing difference, the primary clutch on the 340 has heavier weights to increase the engagement RPM. I believe the 6DH8 needles are leaner than the 6DH3 needles. I would drop the "E" clip 1 notch to richen it up and go from there, watching the plug color.

[deerefanatic]

I noticed that the needles are already dropped a notch.. So we'll see how that works out...... Gotta get some daylight to go play in......