600 ci NA build
#81
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Joined: Jul 2004
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From: chicago
I remember following "BUP"s 665ci builds last year. I believe his cam was a 267/271 114 LSA, with .775 lift. peak HP occured at 5800RPM. I'd think to squeeze another 700+ rpm out of it, the lift and duration would need to go up a decent amount. He was running a smaller valve/head though.
#84
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Joined: Mar 2012
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From: Cape coral, FL
I remember following "BUP"s 665ci builds last year. I believe his cam was a 267/271 114 LSA, with .775 lift. peak HP occured at 5800RPM. I'd think to squeeze another 700+ rpm out of it, the lift and duration would need to go up a decent amount. He was running a smaller valve/head though.
nice numbers. How many hours are on this engine? How does it perform in the boat? What's the benefits of a big NA vs say a 540 with an 871?
#85
#87
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From: NW Michigan
SC will likely be easier on valvetrain parts but then again all depends on what cam choice is also. Merc 900 sc and up for instance Every 50-75 hrs springs, lifters, etc.replacement. Could go with less aggressive hydraulic but..
#88
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Joined: Mar 2012
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From: Cape coral, FL
Less time spent "fueling" up with NA for sure. Lol... My partner and I both had same 92 challenger's boats with twins etc however he had 525 SC's and I had revved up 330's on roids deal. Identical top end speed and acceleration however he consumed well over 30% more fuel and I think we all know why...
SC will likely be easier on valvetrain parts but then again all depends on what cam choice is also. Merc 900 sc and up for instance Every 50-75 hrs springs, lifters, etc.replacement. Could go with less aggressive hydraulic but..
SC will likely be easier on valvetrain parts but then again all depends on what cam choice is also. Merc 900 sc and up for instance Every 50-75 hrs springs, lifters, etc.replacement. Could go with less aggressive hydraulic but..
i would think when you're talking big cube vs blower. Say 900-1000 range fuel isn't an issue. As one poster said the big cube was so hard on parts they were pulled and gone through every 30 hours. We aren't talking 550 range. So if big cube is so hard on parts why would it benefit over blower app which we know can go 300+ hours.
#89
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Joined: May 2009
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From: Chicago, IL; Onekama, MI
Less time spent "fueling" up with NA for sure. Lol... My partner and I both had same 92 challenger's boats with twins etc however he had 525 SC's and I had revved up 330's on roids deal. Identical top end speed and acceleration however he consumed well over 30% more fuel and I think we all know why...
SC will likely be easier on valvetrain parts but then again all depends on what cam choice is also. Merc 900 sc and up for instance Every 50-75 hrs springs, lifters, etc.replacement. Could go with less aggressive hydraulic but..
SC will likely be easier on valvetrain parts but then again all depends on what cam choice is also. Merc 900 sc and up for instance Every 50-75 hrs springs, lifters, etc.replacement. Could go with less aggressive hydraulic but..
#90
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Joined: Feb 2009
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From: NW Michigan
Crane did the grind for merc. According to norm at Competition Fuel Systems they changed (softened) it up the at some point.
Sounds like OT been down the blower road and prefers alternative route. Something different than the norm these days. I would guess the way he's going about it he will have pretty stable valvetrain as long as he stays up on some simple routine maintenance.
Ya he could build a pair of 540's with 871's/1071's and 651 hyd roller cam....
Sounds like OT been down the blower road and prefers alternative route. Something different than the norm these days. I would guess the way he's going about it he will have pretty stable valvetrain as long as he stays up on some simple routine maintenance.
Ya he could build a pair of 540's with 871's/1071's and 651 hyd roller cam....
Last edited by getrdunn; 01-02-2018 at 12:37 PM.


