Guess what engine part this is from a Chevy powered boat
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He could have maybe bought a special marine grind for all I know.
The reason he bought this replacement engine to begin was he bought new valve covers for the original 454 but did not use any of the breather set up and it ended up forcing all the oil out of the engine and it seized up. I told my buddy to tell him to buy a marine engine that is already dyno tuned and ready to drop in instead trying to save money by attempting to assemble one himself. I wonder which way would have cost more in the long run.
The reason he bought this replacement engine to begin was he bought new valve covers for the original 454 but did not use any of the breather set up and it ended up forcing all the oil out of the engine and it seized up. I told my buddy to tell him to buy a marine engine that is already dyno tuned and ready to drop in instead trying to save money by attempting to assemble one himself. I wonder which way would have cost more in the long run.
My buddy is going to take this guy's block in to get it checked out for him, apparently all the caps are blue from getting so hot.
Also this guy wants to buy a new lightweight crankshaft and wants to go with a 4.375 stroke to make it a 556 CI. instead of a 540.
I told my buddy to tell him that will give him a terrible rod ratio with a 9.8 deck block, I don't know anything about boat applications but it seems to me he is already limited with his 269 cc oval port heads, dual plane intake and small 4150 carb.
Also this guy wants to buy a new lightweight crankshaft and wants to go with a 4.375 stroke to make it a 556 CI. instead of a 540.
I told my buddy to tell him that will give him a terrible rod ratio with a 9.8 deck block, I don't know anything about boat applications but it seems to me he is already limited with his 269 cc oval port heads, dual plane intake and small 4150 carb.
This is one of the burnt main caps from the guys boat engine (they were all about this color) it is a Dart Big M block that was severely overheated from internal metal to metal contact.( multiple mains spun)
We took the block in to the machine shop and my buddy heard back Today that this guys block is trashed it has stress cracks throughout the entire webbing, we knew it had to be bad because the main caps we no longer snug at the registers so now it is just a really expensive boat anchor.
Wow just wow I dont even know what to say about this whole thing. That is just a big mistake! You just cant idiot proof an idiot. Engine building isn't just throwing on parts after parts. I have no doubt he didnt blueprint the engine before even considering a final assembly. The minute I read that the mains heated up I just said to myself oh yea this block is toast. Boat engines and car engines are two different deals. Boat engines like a cam grind that produces more power up top on the rpm band. Rather than car engines. ( speaking by comparison). Its easy to think if it costs more its better.
Why would he even consider duilding anothe. I dont even know. It sort of bothers me lol. I know what it takes to build an engine right, and then I see this happen to a 540cid 😵
Why would he even consider duilding anothe. I dont even know. It sort of bothers me lol. I know what it takes to build an engine right, and then I see this happen to a 540cid 😵
I have an offshore boat with a BBC and a Weiand blower, I have also built a Pontiac powered jet boat in the past. First off, it takes a little thought when building a boat engine package. Things like bearing clearance, CR. and cam profiles are quite specific to marine applications. Forged parts and oil coolers are also "must have" items. Marine engines work hard, they are always under load. The person that owns that engine talked about above will probably run out of money before a suitable engine is built, and end up hating boats and sell the project boat at a loss on CL before he understands what went wrong in the first place.
Right now his extruded intake manifold ports are bigger than the ports on his heads so there is a ledge all the way around disrupting flow so instead of just buying bigger heads to replace the Merlin 269 oval ports (as suggested by everyone) he wants to get these extrude honed to the max thinking they will out flow 320+ heads and the above picture are the gaskets he wants to use to match it to.
He just does not understand why this won't work and he disagrees when everyone tells him so even World Products who make the heads.
By the way this guy has a good paying job and is not married so he does have the money but how many attempts and failures do you need before you accept you don't know what you are doing, I guess we will see how long engine number 3 runs
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