06-24-2008, 08:57 PM #1
New owner of a 1390 need more speed...
looking to get it really going, havent pick it up yet but has...
Group K, 91 octane, 1390CC Big Bore Kit (see details at GroupK.com)
GroupK Thrust Bushing in Pump.
Advent Data Tach with EGT probes in exhaust manifold.
Advent Ignition with four timing curves.
Riva D-Plate, exhaust resistor, free-flow kit, intake grate and ride plate.
Solas 14/20 prop modified by Speed Freaks.
Remote carb adjustors, T handles on low speed.
Pro-tec reed stuffers.
Blue Printed Pump Stator.
Looking to get this over 80, point me in the right direction, thanks
06-24-2008, 08:59 PM #2
06-24-2008, 09:01 PM #3
06-24-2008, 09:10 PM #4
You are going to need some reeds
06-24-2008, 09:12 PM #5
you would think it would have the reeds, but will check it out
06-24-2008, 09:20 PM #6
05/06 new style pump with a repitched Dynafly prop 14/25???
48mm NOVI Carbs
83.3 mph at the bug
06-24-2008, 09:22 PM #7
how much mph will the pump put out, have a spare jims.
06-24-2008, 09:38 PM #8
Make sure your carbs are jetted correctly. Group K sets them up with stock jetting which seems to run very lean. Most members here with Group K kits have re jetted with much larger jets.
06-24-2008, 09:44 PM #9
Do you know what kind of plate, grate, tabs etc. are on the boat??
Tunnel needs to be reinforced if not and proper shoe placement is critical before you get to excited on making more power. At least IMO.
06-24-2008, 09:48 PM #10
yea, gonna take care of all the basic stuff before going crazy, riva 1200 plate and grate is all that is listed, going to get it tomorrow and will figure it out.
yea he rejetted the carbs. he has been running this 1390 for awhile. says 73 range. looking for 80
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