6.2 Mercruiser blown up 4th tiime!!!!! Help
#22
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Location: Okanagan Falls BC. Canada
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Depends on your cam's duration, overlap etc.....
Had to have a riser custom made for ZZ572 engine to stop reversion.Over 400 hrs on the engine so far with no reversion issue. I suggest to do the same for your 454.
Had to have a riser custom made for ZZ572 engine to stop reversion.Over 400 hrs on the engine so far with no reversion issue. I suggest to do the same for your 454.
#25
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there is no replacement for displacement. however the a 6.2 is much lighter than a big block. if you have 385 out of a big block and 325hp out of a small block the power to weight ratio will be a wash.for the most part plus you will need to buy new exhaust etc etc. in my opinion i would build your small block from scratch put a good crank and rods, pistons and heads, you could very easily rebuild a small block with a stroker kit and make 400 to 500 hp and still be pretty reliable.
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Anyone got any info on what I should expect to see out of the new 454MAG when it goes in? Machine shop setting it up to be carburated and around 475hp. Boat wieghs 4100lbs and used to have 320 horse and could get up to 55 mph with 19 pitch 3 blade
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My 496 has a much steeper angle on the thru hull exhaust elbows/tubes. I've heard of people having the same problem as you and it was solved by installing a taller riser.
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Yes the weight wash out is why Mechanic suggested building Carb version with 475 HP only after I refused to build another 6.2 or SBC. He also suggested building up a small block for that same reason, but I got great deal on this 454 MAGMPI motor and couldn't pass it up. I have agreed to let the machine shop put different cam in, and they are also selling me the correct intake for the square port heads that accept carburetor instead of the MPIEFI, Machine shop sais should produce 475 HP done a million times. I just dont know how much more fast that should be so when I see trial the boat after the build I dont really know if its right or built wrong. Plus I am little concerned that maybe to much power for my small 242 ???????