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Old 08-17-2014, 10:11 PM
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Originally Posted by Goin Nuts
Thanks well starboard motor took a dump so have to do one figured with 700 hrs just do both and bump them up...
Do those drives and transom assemblies also have 700 hours on them? If so, better budget for a rebuild, as you will probably be on borrowed time. What about the exhaust? Stock Merc with 700 hrs too?

Originally Posted by Goin Nuts
... I was told if I was easy on the sticks drives would hold up for a while...
Kind of like asking John Holmes to only use four inches...
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Old 08-18-2014, 07:04 PM
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I built a 540 using the MPI intake setup and it made 567hp. That seems to be about the end of what they will do without some heavy modifications. You would probably be better off to go with an aftermarket EFI setup if you are wanting more power than that.
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Old 08-18-2014, 08:34 PM
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What were you using for injectors/heads/etc? Any other details?
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Old 08-19-2014, 06:38 AM
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That's why I'm here looking for that input thanks
Originally Posted by Cole2534
What were you using for injectors/heads/etc? Any other details?
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Old 08-19-2014, 07:04 PM
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I used the stock injectors and fuel pump setup, I just increased the fuel pressure a few PSI. Flat top pistons, Madera custom camshaft and a set of Edelbrock marine heads. Fuel was not the problem, it was air. Eddie Young tuned it for me on the dyno and we could watch it go very rich at higher rpm. Had to take away a lot of fuel up top. Just can't get enough air through the MPI intake.
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Old 08-19-2014, 07:10 PM
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Originally Posted by snapmorgan
I used the stock injectors and fuel pump setup, I just increased the fuel pressure a few PSI. Flat top pistons, Madera custom camshaft and a set of Edelbrock marine heads. Fuel was not the problem, it was air. Eddie Young tuned it for me on the dyno and we could watch it go very rich at higher rpm. Had to take away a lot of fuel up top. Just can't get enough air through the MPI intake.
May use a carb what cam & head part numbers what were your end results?
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Old 08-19-2014, 08:02 PM
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I would suggest Dart Iron Eagle heads if your on a budget. Also Bob M but a hydraulic cam. You should be able to get 550+hp on the MPI set up. 700 HP is a WHOLE different game.

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Old 08-19-2014, 08:05 PM
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Problem with 700 is now you have to change at least to an XR.

Beyond 500-550 is a big milestone for a Bravo boat.
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Old 08-27-2014, 12:49 PM
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It's not necessarily about the specific engine parts but also the need to consider the drive train, props, fuel system, etc. that all combine to achieve your goal. You mentioned some attributes, but not a specific goal. Is it absolute peak power at the max end of your budget? Max top speed? Good all around setup with another 700hr life span? Power house engine with a weak driveline that might leave ya stranded? Beat your best buddy's boat? Poker run champ?

At the end of the day, you don't drive around in a dyno room or build an engine to a forum approved specification. Dyno sheets, CID, Brand 'X' headset, porting by God himself, $$$ invested, hours spent, yada yada, in and of themselves, don't mean a whole lot. Set the proper expectations & goals that fit with your budget and you'll likely avoid many pitfalls when getting into the performance engine game.
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Old 08-28-2014, 06:14 AM
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Ok so went to machine shop yesterday block has to be bored 40over but they are tell I am not going to gain much by stroking it 1 hp per cubic inch but I was thinking there would be better torg curve so any input at this point would be appreciated block will be ready Tues.guess would like to know what the gains would be and is 700hp with reliability a realistic .. anyone have rm builders email address
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