thinking about LS swap from twin 454???
10-27-2018 | 09:48 PM
#12
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Joined: Mar 2012
Posts: 4,189
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From: Cape coral, FL
I’m dying to see a 650+ 454 cu in engine live in a boat. There is someone in the swap shop and on Facebook selling a pair of LS marine engines. Think they were in a sunny. Might be a good person to talk too
here it is
416ci LS3 motors 25k
here it is
416ci LS3 motors 25k
Last edited by Crude Intentions; 10-28-2018 at 12:28 AM. Reason: Wrong number
10-27-2018 | 10:15 PM
#13
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From: Grand Rapids, MI
I ran 600HP 454's for 6 yrs with no issues.(cruise@4800 RPM, 6500RPM@WFO) I then detuned them to ~550-575Hp for another 5 yrs. Fully refreshed them this summer and I run 87 octane.
416ci LS3 motors 25k
And Dennis's engines are a good package.
Last edited by Rookie; 10-27-2018 at 10:22 PM.
10-27-2018 | 11:37 PM
#15
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From: On A Dirt Floor
10-27-2018 | 11:47 PM
#16
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From: On A Dirt Floor
10-28-2018 | 01:38 PM
#17
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From: chicago
680 is a stout number for a NA 454/468. Your asking for almost 1.5hp per cubic inch. I doubt that setup will be very user friendly.
Most marine high performance endurance builds, are usually in the 1.0-1.2hp per ci range. I certainly dont see 680hp with that cam, dual plane intake, and marine exhaust manifolds. At least not on a dyno thats actually calibrated.
Most marine high performance endurance builds, are usually in the 1.0-1.2hp per ci range. I certainly dont see 680hp with that cam, dual plane intake, and marine exhaust manifolds. At least not on a dyno thats actually calibrated.
10-28-2018 | 01:46 PM
#18
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From: Murrayville Georgia
680 is a stout number for a NA 454/468. Your asking for almost 1.5hp per cubic inch. I doubt that setup will be very user friendly.
Most marine high performance endurance builds, are usually in the 1.0-1.2hp per ci range. I certainly dont see 680hp with that cam, dual plane intake, and marine exhaust manifolds. At least not on a dyno thats actually calibrated.
Most marine high performance endurance builds, are usually in the 1.0-1.2hp per ci range. I certainly dont see 680hp with that cam, dual plane intake, and marine exhaust manifolds. At least not on a dyno thats actually calibrated.
10-28-2018 | 02:55 PM
#19
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From: Cape coral, FL
that seems the way to do it here. Awesome power claims but boat is no faster than another one with a 500efi. Of course they have all the excuses in the world as to why it isn’t as fast. Lol.
10-28-2018 | 04:23 PM
#20
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From: Grand Rapids, MI
After doing the 600HP to now ~550-575HP my boat is faster with less HP. I believe this is because I brought my pk TQ and HP down and closer together. I couldn't believe how far the splits would be on a 680HP 454. When cam testing in the race boat the highest HP dyno "King" camshaft wasn't always the best or fastest in the real world boat.
Oh, and my 454's are so far 4mph faster than the 500efi's that were original to my boat.
Oh, and my 454's are so far 4mph faster than the 500efi's that were original to my boat.
