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bobv

Contributing Member
I didn't want to get off track with hoss 1234 problem so I am starting a new thread After installing two new distributors and coils I got 3300 rpms out of the boat. 4 people full fuel and full water. I was hoping to get closer to 4000 rpms.
Any suggestions for tweaking the motors. 1980 Marinette twin 225 chryslers original carbs? The motor responds quickly and crisp just disappointed in top end.
Thanks
Bob
 
is the boat propped with the original props? may want to check that and look a lil bit into differant pitches, if the engine is running as good as u say it is i would think prop pitch and tab adjustment would be about it...
 
I second Andy's point about the props being as far as you want to go. Unfortunately, pulling more top end power and rpms out of a 318 comes at a cost that a boat like yours probably can't afford. In other words, you'd give up performance where your boat really needs it (low-end/mid-range).

A 225 in a runabout/ski boat is a slightly different story.
 
if everything else is the same & the boat hit 4000 rpm's before the new distributors, then they would be the first place to look, although being full of fuel & water would add another 2000 lbs or so of weight & cost a couple of hundred rpm, I would look at the timing, are you getting the full 26 - 28 degrees of advance? Get hold of an adjustable timing light & try timing the motors at 2500 rpm to make sure your getting the full advance. 2 or 3 degrees can make a big difference.
 
I couldn't get that much from the old distributors i'm sure the props are right I need to check for build up on the bottom.
Thanks
Bob
 
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