Merlin 345 Grumpy Jenkins flow numbers... Stock and ported??
10-15-2018 | 06:26 AM
#13
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From: Fredericksburg, Va
I do not know your combo, but 345's are large for normal size(468-509) boat engines, unless I'm off on this opening up the ports a bit more not going to give you much at the RPM's we usually see ?
10-15-2018 | 08:36 AM
#14
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From: Olmsted Falls,Ohio Marblehead,Oh
I am 548CI, they are still a tad large to me but these engines were also done 20 years ago before all the good heads we have now... opening up ports and making better flow don’t always happen at same time, you can gain flow without hogging them.
10-15-2018 | 06:28 PM
#15
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From: NW Michigan
10-16-2018 | 11:00 AM
#17
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From: St. Pete Beach, FL
10-16-2018 | 12:21 PM
#18
Frank's Marine Service
Joined: Sep 2002
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From: Elkton, MD
How old are the heads? The decks on those heads were notorious for caving in on the combustion chambers and getting holes. Had it happen to me two times on my engines many many years ago. If the heads need seats and guides anyway it might not be worth the fuss to fix them and then have them ported. But I guess you'll find out soon enough!
