Thread: which block

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i am about to start a new build-up for my mud truck and here is my dillema. i have 4.250 bbc crank and both tall and short deck blocks. since i have to buy pistons and rods, which block should i start with. bottom end torque is important but rpm is also needed (6500 rpm would be great) i realize the tall deck is a more expensive build but cost is not the real issue here, i'm after both power and durability. any help or suggestions would be appreciated.

I'll yield to Pat McCarthy on the BBC builds. He'll be along shortly. The one thing that comes to mind is that header clearance can be problematic with the tall deck and off-the-shelf headers.

(Quote Clinto) i realize the tall deck is a more expensive build but cost is not the real issue here, i'm after both power and durability. any help or suggestions would be appreciated.

With that being said, the tall deck is the way to go.

Use the tall deck, you'll be able to go with a longer rod which will reduce side loading on the cylinder walls and make your engine SLIGHTLY more reliable.

well the tall deck is a 4 bolt main not to big of a deal . like said you can run 400 longer rod with it but that is not worth the added work to build the 427 to 496 But i would put a 4.500 crank in it if i was doing the tall deck and just use the 496 with the 9.800 deck block i have built many 496 and bigger with 4.600 bore blocks 565 cid out of the 9.800 deck block there just fine with the 6.385 rod BUT at 7500+ rpm and very hi cr with a very HI load the pistons do see some trigger on the pistons skirts you should build this for MAX TQ and not worry about needing to run hi rpm it will live alot longer if i was going to run all day long at 7000+ rpm i would go longer rod BUT you can still go longer with the 496 then 6.385 in the short deck 9.800 block . with alot of Nos or alot of boost then i may look at the tall deck so i could have a better ring pack for Nos and more CH on the piston a bit longer rod hope this helps ?

this engine will see moderate nitrous use (under 200 shot) about 25% of its runs. the truck runs on motor for the first three classes then gets sprayed in open class. from what you are telling me the tall deck is probably the better option. will the 4.5 crank work in this tall deck ( i had been told by one shop 4.25 is max in these blocks) if it will work i will buy a 4.5 crank.