100 tall block question

Looking into building a hemi with a screw on it for nhra alocohol funny car. Everyone seems to be running 4.375 bore x 4.375 stroke and 100 tall blocks. What's the advantage and can you run the same combo with a std deck?Not looking to rotate the earth or rev it to the moon just run mid to high 5.70's
Thanks for the info Bob Churchill

 

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Bore x Stroke x +100 Block

This is the exact same combo I run but I have been hearing for some time now that a lot of racers are going to a larger bore and a shorter stroke for an ALCOHOL motor since the burn time of alcohol is shorter than gas or nitro. Shorter burn time = shorter usable piston power stroke with any non-horsepower producing portion of the stroke actually being just a drag on the motor by making the crank drag the piston the rest of the way down. Probably a small difference in efficiency but in todays competition, even a small increase in power is still an increase in power. I am considering going to a 4.4375 bore with a 4" stroke (mainly because the bore size is a big as my sleeves will allow and still leave me sufficient wall thickness) and still have around 495 cubic inches. The +100 block I have is just what I ended up with, not necessarily the best height to use. I also think that a shorter stroke also means less rotating mass, thus probably a higher safe rev limit.
Here I am giving my .02 again. I should probably ask for change back.
Barry

 

actually the BAE combo of choice has been a 4.467 bore for a few years now. I believe it uses a 4.15 stroke. .

 

block

You can always cut the block and sleeves down. Don