Riders report on G3 XL 1978 115 hp and pitched props Riders report on props 35 to 52 Mph 15 pitch water skier dream click for view of 1,000 pound pull carefull do not over rev 35 Mph 17 Pitch Drivers dream, great hole shot lots of roar and great steering control 44-46 Mph 19 Pitch was the best untill we switched to low dome pistons top speed 47 - 48 Mph Not as much steering control 21 Pitch must sell this puppy top speed 52 mph if the wind blows, no touque no roar
dull drive Poor steering control tends to cavitate not usable with low dome pistons. Observations: Using a video camera we noticed that as we increased the prop pitch the back of the
boat climbs out of the water, this accounts for the steering problems and cavitational
increases On other boats this Rising would be an advantage but with the front keel of G3 and
no rising strakes the nose can move you rudely in upcoming rolling waves.
Our G3 begins to rise and fly at 37 mph but one can never truly get her
up on the water as there is no pad or strakes on this hull to hold her there.
(she is a slow boat) Jack plating upwards. We moved this engine up 1.5 inches it looked cool, however in nearly every turn the back of the boat wants to be where where the front just was the exchange occurs rather rapidly. Cool effect - it will scare the crackers out of you too. It won't however go any faster. Part of the Fun of Driving the G3 XL Larson is you must learn how to Her: Overall this Heavy version G3' 1974 - 1977 does not perform well in any task asked
of her for example the boat may turn flat and slide and / or slide tight
it can rise to a bank or it can dig firm into a turn. It all depends
upon the trim and speed, one must learn how to drive this boat. What the boat does do well is place a smile on nearly every party who drives
her, the gleam on their face appear to say. Now let me try her. About the back chrome pole loops As I eluded too above the boat tends to ride high on a turn at some speeds if this
happens when a skier pulls to the side you simply cannot steer and they have
the power to pull the boat over. We fabricated a fix by keeping the rope
at the back the boat while using the advantage of the ski pole. The
pipes where made from Auto muffler pipe folded to a wood template at the muffler
shop. We had them chrome plated at furnature manufacture. They also make it easy to grab the boat at a dock, they look cool too. Bouncing Yep she purposes, at one speed it is very annoying and depends upon the weight of
the riders of the day. The fin on the back of the motor greatly stops this
from occuring. It also improves the hole shot. This
boat snaps high into the air, which is cool except for the fact it then cavitates
and stalls out coming down. One needs to re-shift down with the throttle
to re-grab the water, by that time the show is over. The motor
fin is a must have option for this unit. The change is a 100%
improvement it did not slow this boat hull. 85 Hp to 115 Hp The 85 hp merc we had was cool engine it roared louder and faster than the 115 she
would pin the tach 6,000 plus rpm. We moved up to the 115 as we thougth
the smaller unit would not hold together at those extended RMP's.
About the speed, the 85 Hp did 43 MPH the 115 did 48 MPH there was
not that much of speed increase. The gas consumption went done considerably
however with the purchase of the 115 hp as much of the time the boat was used
for skiing, whearas the 85 had to be gas pinned to pull 1 or 2 salum skiers.
The 115 is about 1/2 throttle. However when idleing shut the 115 hp
off she slups fuel in idle mode. We now shut the engine
off when ever we can it can double your hours on the lake in doing so.
In retrospect I wish we had the selections of props and power trim for the 85 merc,
it was one powerful package. 115 HP Merc 1978 High dome pistons 5, 500 RPM with 17 Pitch 46 MPH 115 HP Merc 1978 High dome pistons 5, 300 RPM with 19 Pitch 48 MPH Prefered 115 HP Merc 1978 High dome pistons 5, 200 RPM with 21 Pitch 52 MPH 115 HP Merc 1978 Low dome pistons 5,100 RMP with 19 Pitch (considerable power loss) We now use the lower pitch 17 5,350 RPM 44 to 46 Mph Note: If your thinking of purchasing a 6 inline Classic Mercury tower of power
move up a few years to 1994 those 115 had power ports cut in the block and
was the older 140 hp units. All other parts same. Our 115 hp is todays
90 HP most likely why we only seen a few miles per hour increase. You
may also consider a 4 cyclinder 85 hp merc it was cool operating machine for this
boat. Happy boating..Got a G3 or XL picture. Drop us a line click here |