525SC Rebuild Recomendations
03-19-2018 | 11:47 AM
#42
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Funny thing is there is no letter after the 1-043, casting is just flat. Is this because it is a Merc application?
I'm also looking at a pair of pro topline aluminum 320 heads, but I've heard they had lots of issues. Would you go for the toplines over the Merlin's in a freshwater boat?
I'm also looking at a pair of pro topline aluminum 320 heads, but I've heard they had lots of issues. Would you go for the toplines over the Merlin's in a freshwater boat?
03-19-2018 | 01:08 PM
#43
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From: chicago
I have never heard of a Merlin cylinder head being used by Mercury.
the 320 pro topline was the same head design as the EQ 320, and RHS 320. I believe when RHS was bought out by comp cams, they had no interest in the iron versions, so engine quest picked them up. Outside of marine and truck pulling classes, theres very little market for bbc iron heads in the automotive world.
the 320 pro topline was the same head design as the EQ 320, and RHS 320. I believe when RHS was bought out by comp cams, they had no interest in the iron versions, so engine quest picked them up. Outside of marine and truck pulling classes, theres very little market for bbc iron heads in the automotive world.
03-19-2018 | 03:03 PM
#45
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From: chicago
03-20-2018 | 12:18 PM
#46
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From: Toronto, Canada
engine build
03-20-2018 | 05:43 PM
#47
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Ok I'm looking at the aluminum heads, can I just turn down the boat by not over driving the blower to try and keep the the HP down if I do heads and a roller?
Last edited by Mohavvalley; 03-20-2018 at 06:12 PM.
03-20-2018 | 06:23 PM
#48
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From: Toledo Oh
03-21-2018 | 01:44 AM
#49
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The stock 525SC pulley is a 3.25" upper and 6.5" lower if I recall correctly. I know it is 2:1 overdriven and stock boost is 5.5#.
Nobody ever made a larger upper pulley than stock that I'm aware of. Not sure what size you have?? I'm guessing 3.12" ??
The splined pulley is NLA so you would have to find a used one or have your blower shaft changed to keyed one.
Nobody ever made a larger upper pulley than stock that I'm aware of. Not sure what size you have?? I'm guessing 3.12" ??
The splined pulley is NLA so you would have to find a used one or have your blower shaft changed to keyed one.
