Mercruiser 383 Re-Power
Michael T
Member Posts: 7,227 ✭✭✭✭✭
Some interesting news from Mercruiser, actually Mercury Re-Manufacturing. For anyone wishing to re-power or up-grade there is another 383 available, this time from mercury. We know that the 454 blocks are no longer being made as I believe are the 496s (not absolutely sure about the 496) so mercury has come-up with a solution. They are offering a 350HP 383 stroked 350 block with full warranty designed by Mercury Racing. IMO 350 Hp is quite conservative for a stroked 383 (we built mine to 380 HP) so it should have great longevity. It has the latest fuel injection, cool fuel lll and laptop portal management. At 932 pounds there is a weight saving and a lot of HP/Torque. The price of 10K seems reasonable as well for such a high-end product. I would think it would be particularly applicable for some of the older single engine Rinker cruisers.
Comments
People talk about HP, but it's nothing if not backed with TQ.. without the twisties there are no ponies.
She runs clean, too... I've never pushed more than a puff out- and would soil the sheets if it ever rolled coal... that means something is bad wrong... plus, there is no reason to draw attention if I don't need to...
but the big blocks.... there isn't much more fun than building and running one, huh? They kick out the torque mucho better than the same $$build in a small block...
Boat Name: King Kong
"Boat + Water = Fun"
I don't care to do anything more to it as everything I've done is for longevity and reliability- others who throw caution to the wind take these motors and pump up to 1500hp and over 2k# of torque...
the slow rev of diesels make them pretty much undesirable in a fast plane boat, but I wonder what would happen if someone purpose built a diesel-to-gearbox just for a specific hull, and what would come of it... translating to HP doesn't deplete the torque like it does on a gasser, and is akin to a big block in that regard (but even better)- but pony to pony, and through the simplicity of gas engines, the diesel has to produce more than twice the HP-to-weight to make it as desirable as far as performance goes... now economy? That's different...
put it like this: On a steady plane and @, say, 32mph and 2800rpm's, a diesel pushed boat encounters a headwind or a facing current- and doesn't drop but maybe 2mph and loads up dropping 150rpm to 2650rpm at the same fuel consumption (all fictitious) - while a comparably equipped gasser on the same hull can hold 32mph and 3300rmp in calm seas, then encounters a head wind or facing current just like the diesel- it drops to 26mph and struggles @ 4000rpm... that is the precise place where abundant torque pays dividends..
same concept as above- except now we'll say the above gasser is a small block, and what was a diesel is now a big block... the big block will suffer more than the diesel, but nowhere near as bad as the small block... when we're talking about gassers, though, we;re talking about fuel as a catalyst, and ratio of fuel to air- you add air to add power not fuel (as in a diesel), but with added air more fuel is needed in pretty close ratio to the air to make it burn properly- too little, it's uncontrollable and will detonate before it's 'sposed to (BOOM)... bad bad bad.. too much and it doesn't ALL burn... bad bad bad.. just right and it burns really fast or explodes really slow, however you want to look at it, and that is good... the big block generally has more piston face and shorter stroke ratio (to piston face)... which makes it respond to throttle quicker and retrieve the torque easier (less labor) than the small block...
but that is why I just spilled all that on your screens... that stoke to piston face ratio...
a squared block has the same piston face to stroke measurement... say, 4" diameter pistons, and 4" long rods... that's the mechanical ratio and depending on the size of the bowl, when added in, the mechanical compression. add camshaft and valve events, and now you can figure out dynamic compression- which is the important one... depending on how you go about it, a 383 can be a squared engine.... (not square as in opposing, but ratio square), and when that happens, you get a really wide and flat torque range.... comparable to a big block... which is why I wanna see the TQ curve on that 383... it may do pretty dang well in a boat, giving great economy, great HP/TQ-to-Weight, and while only producing 350 ponies, more than make up for it while pulling a skier or running into facing current or head wind...
huh... it;s been a while since I puked word salad all over y'alls screen, huh?