Mercruiser engine questions
04-30-2013 | 12:55 PM
#22
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Joined: Jun 2011
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From: Thousand Islands area
Gil manifolds DO help.
They probably are good for 10hp on a 454 Mag, and maybe 12-14hp on a 502Mag.
That puts your 454 Mags at maybe 375 instead of 365, but it technically doesn't change the ENGINE RATING.
Not sure where you're getting the 40hp difference, though unless you're counting the drop from crank rating to prop rating.
It's really irrelevant if you plan to add hop up goodies. Once you change the cam, do some port cleanup on the heads, bore notch the cylinders, and zero deck the block you're going to be well over 400-430hp. You have a good motor to start with.
Just be glad it's not the 330 version, which has weaker bottom end and poor flowing heads.
They probably are good for 10hp on a 454 Mag, and maybe 12-14hp on a 502Mag.
That puts your 454 Mags at maybe 375 instead of 365, but it technically doesn't change the ENGINE RATING.
Not sure where you're getting the 40hp difference, though unless you're counting the drop from crank rating to prop rating.
It's really irrelevant if you plan to add hop up goodies. Once you change the cam, do some port cleanup on the heads, bore notch the cylinders, and zero deck the block you're going to be well over 400-430hp. You have a good motor to start with.
Just be glad it's not the 330 version, which has weaker bottom end and poor flowing heads.
04-30-2013 | 12:57 PM
#23
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Joined: Jun 2011
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From: Thousand Islands area
Like I said do a nada guide run on a 91 fountain fever and it shows 385hp. I guess if the Gill added 10 hp, its possible 10hp might have came from somewhere else.
05-01-2013 | 08:26 AM
#25
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From: Clearwater, Mn
http://www.boatfix.com/merc/Bullet/91/91_16.pdf
Case Closed! This is straight from Mercruiser. Prop HP is 350 on 454 mag/bravo
Case Closed! This is straight from Mercruiser. Prop HP is 350 on 454 mag/bravo
05-01-2013 | 08:35 AM
#26
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From: Thousand Islands area
Ok i looked last night at the performance sheet the day the boat was ran, actually had a time, date, and test drive Actually had Reggies signature there, for those making jokes. It did say 365hp for each engine, so the case is now closed. But I find it funny how Nada, insurance keeps saying their 385s.
05-01-2013 | 08:40 AM
#27
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Joined: Jan 2002
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From: Further South East of Dome Island
Ok i looked last night at the performance sheet the day the boat was ran, actually had a time, date, and test drive Actually had Reggies signature there, for those making jokes. It did say 365hp for each engine, so the case is now closed. But I find it funny how Nada, insurance keeps saying their 385s.
05-01-2013 | 07:55 PM
#28
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Joined: Jul 2011
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From: Pittsburgh, PA
Ok i looked last night at the performance sheet the day the boat was ran, actually had a time, date, and test drive Actually had Reggies signature there, for those making jokes. It did say 365hp for each engine, so the case is now closed. But I find it funny how Nada, insurance keeps saying their 385s.
05-01-2013 | 08:07 PM
#29
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Joined: Jun 2011
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From: Thousand Islands area
yeah i doubt their pricing as it is. If i check my 91 it says 17k for the thing, and I dont think you could fine a running fountain for under 20
05-02-2013 | 05:06 PM
#30
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Joined: Jul 2011
Posts: 237
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From: Pittsburgh, PA
