max rpm

[ram4fun29]

what is the max rpm for a 1985 120 johnson. it is completly stock. can the exhaust be raised on this motor ? and would it help any

[Charlie M]

I have run the 140's at 6700 rpm's before. They only have the larger carbs on them, as compred to the 120's. Those earlier small bore loopers had bridged exhausts and where fairly tall as they came, not so shure I would raise them. Think I measured them before and came up that they where .100 taller than the later 2.0 motors with the full oval exhaust port. The looper motors you can parts change many of the components to boost power without having to grind on the block.

[racer]

If you are not finger porting and want to maintain low end do not raise them.

[ram4fun29]

thanks guys i was told by a dealer not to turn it over 5500 but that seemed low to me .