Merc 377 Scorpion top ends?
08-14-2017 | 12:31 PM
#1
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From: Miami, FL
Merc 377 Scorpion top ends?
I have blue 377 scorpions with 290hrs on them. As far as I know, they had whipples installed at around 100hrs. Looking for when I should do top ends. No current issues, just curious.
Tim
Tim
08-16-2017 | 08:04 PM
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The lift was not .6 something. It was low .5, like .51x/.51x or in that ball park. I've seen the specs just can't fine them. 2.05 and 1.6 exhaust, so yes big on the intake.
08-16-2017 | 08:43 PM
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From: On A Dirt Floor
The 400hpScorpions ?
If so, I found a quote from myself years ago:
If so, I found a quote from myself years ago:
Originally Posted by sb
Run down on the 383cid Scorpion:
6000+rpm rev limit.
hand
5600-6000 rpm recommended operating rpm at WOT
Tunnel ram intake
RHS heads w/ 2.08/1.60 valves
.575, .596 lift HR cam with 1.6 roller rockers
Forged steel crankshaft
forged pistons
9.6:1 compression - 91 octane fuel minimum
CMI headers
In case I made a typo click here: http://sites.mercurymarine.com/porta..._schema=PORTAL
and make sure to click on the .pdf containing the rest of the build info.
6000+rpm rev limit.
hand5600-6000 rpm recommended operating rpm at WOT
Tunnel ram intake
RHS heads w/ 2.08/1.60 valves
.575, .596 lift HR cam with 1.6 roller rockers
Forged steel crankshaft
forged pistons
9.6:1 compression - 91 octane fuel minimum
CMI headers
In case I made a typo click here: http://sites.mercurymarine.com/porta..._schema=PORTAL
and make sure to click on the .pdf containing the rest of the build info.
08-16-2017 | 08:45 PM
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From: On A Dirt Floor
08-16-2017 | 08:53 PM
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Were the scorpions rated 400 horse? Seems like a 383 with sb specs above would be more than 400.
But then again with a bigger boat it seems a big block is faster even if it has less horsepower on paper. Case in point a 415hp 502 is usualy faster than a 400ish horse 383.
But then again with a bigger boat it seems a big block is faster even if it has less horsepower on paper. Case in point a 415hp 502 is usualy faster than a 400ish horse 383.
08-16-2017 | 09:04 PM
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From: On A Dirt Floor
I believe there where different Scorpions..not sure..?????? .that's why I made sure to put up which one I was referencing. The 400HP Scorpions.
And yeh, I agree,most dyno's would show more than 400hp with that set-up...I'm sure. Remember, Merc has to put power ratings where they will sell not only this motor but other motors. ust like the 525EFImaking 560hp or so.
And yeh, I agree,most dyno's would show more than 400hp with that set-up...I'm sure. Remember, Merc has to put power ratings where they will sell not only this motor but other motors. ust like the 525EFImaking 560hp or so.
