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Does anyone have a 2003 Rinker 270 FV with a 383 Mag MPi or larger?

jmichelsjmichels CTPosts: 308Member ✭✭
I am looking to repower in the near future. Love the boat just want a bit more power to get me in mid 40s comfortable or even 50. I know the 383 mag mpi is a drop in for the B3 has anyone gone larger? what fits and works? Currently I have a 350 Mag MPI Horizon. Thanks!

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Answers

  • Handymans342Handymans342 Cape Coral, FLPosts: 6,921Member ✭✭✭✭✭
    I would think you could get a big block in there
  • jmichelsjmichels CTPosts: 308Member ✭✭
    what is drop in the turn key for the bravo 3? like to get something around 400-450 hp NA in there fuel injected and turn key motor. 

  • Handymans342Handymans342 Cape Coral, FLPosts: 6,921Member ✭✭✭✭✭
    I was quoted 4 to 5 G each to convert from Bravo 2 to B3
  • jmichelsjmichels CTPosts: 308Member ✭✭
    sorry i meant installing a big block with a existing b3 that i already have
  • AlswaggAlswagg Posts: 2,275Member ✭✭✭✭✭
    Gear ratio 2.0 26 pitch  
  • Handymans342Handymans342 Cape Coral, FLPosts: 6,921Member ✭✭✭✭✭
    Will it fit Al?
  • Handymans342Handymans342 Cape Coral, FLPosts: 6,921Member ✭✭✭✭✭
    A 496?
  • Michael TMichael T Posts: 6,450Member ✭✭✭✭✭
    A 502 will fit in a 290!
  • AlswaggAlswagg Posts: 2,275Member ✭✭✭✭✭
    Yes a 496 Merc will fit in a 270.  Very very expensive and tight 
  • jmichelsjmichels CTPosts: 308Member ✭✭
    So where would a 383 mag put my 270 in cruising speed and top speed ?
  • AlswaggAlswagg Posts: 2,275Member ✭✭✭✭✭
    Again Merc does not have or make a 383 mpi. Only a carbed version.  350 hp I do believe.  Some can modify but again cost is very expensive 
  • jmichelsjmichels CTPosts: 308Member ✭✭
    Sure they do
  • 212rowboat212rowboat Posts: 2,131Member ✭✭✭✭✭
    jmichels said:
    Sure they do
    nah... Mercruiser makes a 377, not a single 383.  Think stroke, but w/o the bore.

    there are plenty of mercruiser engines that aftermarket builders or shade tree mechanics have stroked and bored to 383, but they didn't 'start' life as such... they usually started life as a 350 or 305...

    depending on family of block, they have to be notched for connecting rod clearance- would you rather a machine shop do that or some fella with a dremmel?  When you get into the realm of stroked engines, you are usually into the realm of folks who haven't thoroughly R&D's the platform.

    383's and 408's are the exception, do a degree, as they've been done a long time and have almost become a standard...     
  • Black_DiamondBlack_Diamond Holland, MichiganPosts: 4,337Member ✭✭✭✭✭
    Just go for that new Merc 9l twin turbo. 1,650hp will leave your guests in the water. 

    2003 342FV "Black Diamond", 350 MAG MPI, 20P 4x4 Props, PC BYC, Holland, MI
  • Handymans342Handymans342 Cape Coral, FLPosts: 6,921Member ✭✭✭✭✭
    Or a merc diesel ohhhhhhh
  • jme097jme097 Algonac, MIPosts: 1,208Member ✭✭✭
    edited February 2016
    Why drop $10k into a 13 year old boat? 
    Boat Name: Knot A Worry
    2007 280 Rinker Express 6.2L B3
  • jmichelsjmichels CTPosts: 308Member ✭✭
    what alternatives are there. rest of boat is in great shape

  • jmichelsjmichels CTPosts: 308Member ✭✭

    jmichels said:
    Sure they do
    nah... Mercruiser makes a 377, not a single 383.  Think stroke, but w/o the bore.

    there are plenty of mercruiser engines that aftermarket builders or shade tree mechanics have stroked and bored to 383, but they didn't 'start' life as such... they usually started life as a 350 or 305...

    depending on family of block, they have to be notched for connecting rod clearance- would you rather a machine shop do that or some fella with a dremmel?  When you get into the realm of stroked engines, you are usually into the realm of folks who haven't thoroughly R&D's the platform.

    383's and 408's are the exception, do a degree, as they've been done a long time and have almost become a standard...     
    jmichels said:
    Sure they do
    nah... Mercruiser makes a 377, not a single 383.  Think stroke, but w/o the bore.

    there are plenty of mercruiser engines that aftermarket builders or shade tree mechanics have stroked and bored to 383, but they didn't 'start' life as such... they usually started life as a 350 or 305...

    depending on family of block, they have to be notched for connecting rod clearance- would you rather a machine shop do that or some fella with a dremmel?  When you get into the realm of stroked engines, you are usually into the realm of folks who haven't thoroughly R&D's the platform.

    383's and 408's are the exception, do a degree, as they've been done a long time and have almost become a standard...     
    https://www.mercurymarine.com/en/us/engines/inboard-and-sterndrive/remanufacturing/plus-series-bravo-sterndrives/
  • 212rowboat212rowboat Posts: 2,131Member ✭✭✭✭✭
    jmichels said:
    remanufactured.... not new.  rebuilt. bored block likely due to worn cylinder wall on used block.  not a thing wrong with them, but you'll notice they are Mercury Marine, and 'based' off of the Mercruiser line, they are not Mercruiser even though they're built by the same people.  
  • jmichelsjmichels CTPosts: 308Member ✭✭
    i see makes . sense. I knew they were rebuilt and mercury marine is just a division of mercury for there remanufactored stuff.

    I guess my question is will the computer adjust and add fuel and timing if the engine calls for it or does it have set parameters and maximum values its programmed to do? Reason I ask because its very easy and affordable to pull my current 350 mag and have a machine shop , rebuild it into a nice stout 383 stroker. But if computer wont give it the extra fuel, timing etc it can take then its useless....

  • 212rowboat212rowboat Posts: 2,131Member ✭✭✭✭✭
    edited February 2016
    well now... this is where it get's interesting. 

    yes... and no... no and yes... and maybe... 

    your computer trims for a known displacement but it varies across the temperature and MAP/MAF spectrum.  It's rich at cold start up, and because that's when it's a really really bad time for a pre-det... rich is actually harder to ignite than lean, and therefor it is less likely to ignite under pressure, but requires spark... 

    it's expressed in terms of duty cycle or sometimes called pulse width of the injector, and is a control of the PCM/ECU and how long the injector gate stays open. and when.  mostly, how long it's open, though.  

    your engines PCM/ECU is capable of trimming for the added displacement, but so long as it thinks it's displaced less, it will only provide the fuel for that displacement... so yes and no... it doesn't have o2 sensors to sniff the exhaust and trim accordingly, but it will still run albeit lean... so no and yes... it can be adjusted, but requires a PCM flash- which to my knowledge (calling all experts, Al, namely) there is no way for us to do it... So.. maybe... 

    but here is the thing... 

    you have a known fuel pressure at the rail that is closely regulated to 45psi.  You have specific injectors that deliver a precise volume of fuel to each cylinder.  I'm thinking they are around 26# injectors, but I don't know that for sure... they may be 24# with a wider pulse width/duty cycle, or they may be 28# w/ shorter duty cycle/pulse width... but within this 'game' is your salvation... 

    using 24# injectors as a rule (which I've already said I don't know what yours are), they should deliver somewhere close to the range of 248cc to 258cc per minute.  that is their capability @ 45psi.... you need more fuel... so.. look past the pound (#) rating of the injectors and get into the specific delivery in cc's per minute.  Your pressure isn't going to change... you can't flash the computer (easily or economically)... but you can increase the size of the injector to somewhere in the 25~26# range (or better said in the 260ish cc per minute to 280ish cc per minute)...

    so... go find some injectors that work for your application... you'll be bound by several things- one is ohms, the resistance has to match, another- is stack height and diameter... another is maintaining the spray characteristics while effectively increasing the diameter of the hole(s) the fuel squirts from... likely only backseated to ohms is connectors- EV1 or EV6? you can buy adapters to interchange these, but most folks have bad luck with these as they sometimes alter (increase) the resistance (ohms). 

    Bruce at FiveOmotorsports will hook you right up... or, look for a chart that compares weight (in pounds) to cc's delivered and to stoich @ x cubic inch displacement under known atmosphere and operating temperature...

    my guts tell me you'll be jumping up a single #(pound), but you're going to want to select a 'light' pound, or one that falls on the shy side of the cc scale... this is where an expert like Bruce can help... the straight up best injector person I've ever met on this subject is a fella named Sean, but known as 'hemifever', and he may help you out too... google for him and you'll find his email...  

    remember one thing, though- you'll want to err on the side of caution, and run a little rich rather than lean.. if your current injectors are on the heavy side (in cc's) of a # rating, you may want light side rated #'s TWO #'s higher.... 

    follow? 
  • 212rowboat212rowboat Posts: 2,131Member ✭✭✭✭✭
    i rec you write Sean, and tell him drew said to get his act together and tap the marine mercruiser flashing market... he's very well known in mopar circles. 
  • Michael TMichael T Posts: 6,450Member ✭✭✭✭✭
    Latest BoatTest Magazine article: Mercury Remanufacturing 383 stroker,  350 HP,  390FP of torque, high rise intakes,  MPI,  latest 555 ECM,  Smart Craft compatible.  Available with 3 year Mercury warranty. Looks good to me! 
  • AlswaggAlswagg Posts: 2,275Member ✭✭✭✭✭
    Well you might not like this but here it goes.  Lol.  I would not recommend a stroked out small block for the boat in question.  In fact I would recommend finding a used 496 8.1lt.  Much lower operating rpm better fuel economy at 30 to 35 mph.  I have a 377 mpi with 1.6 ratio rockers in a jeep but I would much rather have a 496 mpi 
  • jmichelsjmichels CTPosts: 308Member ✭✭
    well now... this is where it get's interesting. 

    yes... and no... no and yes... and maybe... 

    your computer trims for a known displacement but it varies across the temperature and MAP/MAF spectrum.  It's rich at cold start up, and because that's when it's a really really bad time for a pre-det... rich is actually harder to ignite than lean, and therefor it is less likely to ignite under pressure, but requires spark... 

    it's expressed in terms of duty cycle or sometimes called pulse width of the injector, and is a control of the PCM/ECU and how long the injector gate stays open. and when.  mostly, how long it's open, though.  

    your engines PCM/ECU is capable of trimming for the added displacement, but so long as it thinks it's displaced less, it will only provide the fuel for that displacement... so yes and no... it doesn't have o2 sensors to sniff the exhaust and trim accordingly, but it will still run albeit lean... so no and yes... it can be adjusted, but requires a PCM flash- which to my knowledge (calling all experts, Al, namely) there is no way for us to do it... So.. maybe... 

    but here is the thing... 

    you have a known fuel pressure at the rail that is closely regulated to 45psi.  You have specific injectors that deliver a precise volume of fuel to each cylinder.  I'm thinking they are around 26# injectors, but I don't know that for sure... they may be 24# with a wider pulse width/duty cycle, or they may be 28# w/ shorter duty cycle/pulse width... but within this 'game' is your salvation... 

    using 24# injectors as a rule (which I've already said I don't know what yours are), they should deliver somewhere close to the range of 248cc to 258cc per minute.  that is their capability @ 45psi.... you need more fuel... so.. look past the pound (#) rating of the injectors and get into the specific delivery in cc's per minute.  Your pressure isn't going to change... you can't flash the computer (easily or economically)... but you can increase the size of the injector to somewhere in the 25~26# range (or better said in the 260ish cc per minute to 280ish cc per minute)...

    so... go find some injectors that work for your application... you'll be bound by several things- one is ohms, the resistance has to match, another- is stack height and diameter... another is maintaining the spray characteristics while effectively increasing the diameter of the hole(s) the fuel squirts from... likely only backseated to ohms is connectors- EV1 or EV6? you can buy adapters to interchange these, but most folks have bad luck with these as they sometimes alter (increase) the resistance (ohms). 

    Bruce at FiveOmotorsports will hook you right up... or, look for a chart that compares weight (in pounds) to cc's delivered and to stoich @ x cubic inch displacement under known atmosphere and operating temperature...

    my guts tell me you'll be jumping up a single #(pound), but you're going to want to select a 'light' pound, or one that falls on the shy side of the cc scale... this is where an expert like Bruce can help... the straight up best injector person I've ever met on this subject is a fella named Sean, but known as 'hemifever', and he may help you out too... google for him and you'll find his email...  

    remember one thing, though- you'll want to err on the side of caution, and run a little rich rather than lean.. if your current injectors are on the heavy side (in cc's) of a # rating, you may want light side rated #'s TWO #'s higher.... 

    follow? 
    I follow you. . I actually drag race cars and build engines, tuning etc.  So very familiar with all that you said however one caveot.  Can't just throw in bigger injectors without rescaling the values . I guess if you didn't it would just dump more fuel but computer thinking it's the same. Kind of recipe for disaster not being able to monitor and control the AFs and ignition timing or KR. Sounds like best option get a BB and just do carbed.  Done
  • Mike_GMike_G Lake St. ClairPosts: 256Member ✭✭✭
    edited February 2016

    What about the "383 MAG bravo 4V"?  350HP, 429ft/lb.  370HP 456ft/lb with the same manifolds that came on the "Scorpion" 383 from Mercury.  More torque than carb 502.  Light weight compared to a BB.

    https://www.mercurymarine.com/en/us/engines/inboard-and-sterndrive/remanufacturing/plus-series-bravo-sterndrives/

    Are the small blocks not good for high load/mid RPM use? -=Mike G.

    2014 Rinker 260EC


  • AlswaggAlswagg Posts: 2,275Member ✭✭✭✭✭
    Big blocks are much better for heavy loads. This is just one reason why Merc does not use the 6.0 lt and builds their own 8.2 lt  not a GM engine but Merc only. Lower rpm and higher torque in the usable rpm range.
     Don't go backwards to a antiquated carb stick with a fuel injected engine.  
  • Michael TMichael T Posts: 6,450Member ✭✭✭✭✭
    Any time I could fit a big block into the engine bay I would. There is no substitution for cubic inches when needing torque to wrestle a boat onto plane and keep it there at lower RPMs. My 2014 Rinker EC 360 was available from the factory with 350 Magnums,   377 Magnums or 502 Magnums. Obviously,  I chose the 502s. If I didn't have room for a BB I'd go 383.
  • AlswaggAlswagg Posts: 2,275Member ✭✭✭✭✭
    Agreed Michael  If you do with a big block remember to also get a new big block Y pipe.  Otherwise easy install swap 
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