How I can make a 454 to 540?
#2
21 and 42 footers
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You can't.....not without spending stupid money. It would cost less to buy one and sell yours. The intake, heads, crank, rod, pistons, fuel supply, exhaust, ignition would all have to be replaced.....the block is really all your re-using.
#3
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not if your doing a stroked 540 short deck motor. but im not sure if you can stroke a 454 or if it can only be done on a 502 based block. im pretty sure you can remap the computer but not sure if the fuel supply pump is big enough.
Last edited by 88bullet; 11-01-2013 at 04:43 PM.
#4
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Not many 454 (if any at all) blocks have the wall thickness to bore to 4.500. You can put the same 4.25" stroke crank though and have a 496 if you bore to 4.310.
#5
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You need to start over. I had a 502mpi in a donzi and when I wanted to go to a 540 short deck I needed to start fresh. The bore needed is too much for a standard block and the stroke will side load the cylinder walls more than any decent engine builder would recommend.(IMO)
#8
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You need to start over. I had a 502mpi in a donzi and when I wanted to go to a 540 short deck I needed to start fresh. The bore needed is too much for a standard block and the stroke will side load the cylinder walls more than any decent engine builder would recommend.(IMO)
#10
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Running a internally balanced 4.25 crank requires going to 6.385 or longer rods to clear the counterweights which helps rod/stroke ratio and piston side load issues. Going to the 6.535 rod with the 4.25 stroke results in a better rod/stroke ratio than a stock 454 or 502 but works best in a tall deck block. Scat did make a cast externally balanced 4.25 crank that worked with 6.135 rods but I don't know of anyone actually running one.
There are tons of GM blocked 540's out there but that's not to say that a Dart block isn't the way to go if you are starting from scratch. I think it is safe to say that not one of those 540's started with a 454 block. I did however know of a 565 that started out as a GM 427 tall deck truck block.
There are tons of GM blocked 540's out there but that's not to say that a Dart block isn't the way to go if you are starting from scratch. I think it is safe to say that not one of those 540's started with a 454 block. I did however know of a 565 that started out as a GM 427 tall deck truck block.