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Discussion Starter #1
What are all the advantages of the 427 tall deck?? Max stroke,cubic inches available?
Are the cranks any good?
 

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Some guy
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What are all the advantages of the 427 tall deck?? Max stroke,cubic inches available?
Are the cranks any good?
You can run the longer rod and change the rod angle some. Many times you can drop a 4.250" stroke crank in without grinding the block, depending on which rods you use, and the early truck blocks had thick cylinder walls, allowing bore sizes as large as .125" over (4.375"). With a 4.250" crank, that yields 511 cubic inches. I would suggest having the block sonic tested prior to trying to bore it that far.

I believe the cranks that came in the 427 truck engines were the 6223 forged crank. Not quite as "trick" as some of the better GM 427 cranks, but still a forged piece.
 

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I have a early 427 t/d truck block in the shop here and it needed a ton of grinding to fit a 4.250 stroke crank in it. and i had talked to a few guys that have put 4.375 crank and even one guy that told me they put a 4.500 stroke in one but i have never seen it done first hand but i bet it would need some filler in the pan rails and i think it would be a egg shell kind of a motor. I have a few 454 block that the same stroke 4.250 crank dropped right in.


I will say that i ran a merc 454 block that split between the bottom of the bore and the pan rail from front to rear on the trust side of the block after years of use that was filled to the water pump with block filler and there was nothing left of the engine when we got it back to the dock.I think it is all hit and miss on production blocks and they all need to be sonic checked before dumping any money into.
 

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Bostick Racing Engines
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The largest I have ever built one is 526... 4.375 bore X 4.375 stroke... didn't much like the combo... but that's what the guy wanted. Still was able to get a 6.700 rod in it with a decent compression height piston. But long rod 4.250 strokers are great for this block... I'd sonic if you plan on going past .060 if you plan on running boost, compression, or nitrous... have found a couple that had some thin cylinders... or rather thinner than I would like in order to go .100 or .125.
 

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Discussion Starter #6
I'm thinkin low compression blower short block

today I bolted a turbo 400 to it and stuffed it in a 79 vette for safe keeping.
 

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My tall deck was fine to 4.375 stroke. I didn't chase the bore past .040 over because I didnt need to. I have read 4.5 stroke is capable, but I dont know. Block casting technology was not as top notch and consistent as todays aftermarket blocks. As stated earlier in a previous posts, sonic test. In the corvette, a 4.25 and big bore should really twist that car around.
 
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