Oversquare or undersquare for a 427?
#1
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Oversquare or undersquare for a 427?
Gents,
Contemplating options on getting my high school truck rolling again. It's a pro streeted 55 chevy. I have always wanted to drop a 427 in it. I'm wanting to turbo it as well. Want at least 750whp with the option to go 1K.
I tried searching, but couldn't find what the best setup would be for the engine build. Thoughts on more stroke vs more bore? Might do an iron block as the truck weighs a ton already.
What are the benefits of doing different displacements/bore-stroke combos?
TIA
Contemplating options on getting my high school truck rolling again. It's a pro streeted 55 chevy. I have always wanted to drop a 427 in it. I'm wanting to turbo it as well. Want at least 750whp with the option to go 1K.
I tried searching, but couldn't find what the best setup would be for the engine build. Thoughts on more stroke vs more bore? Might do an iron block as the truck weighs a ton already.
What are the benefits of doing different displacements/bore-stroke combos?
TIA
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What exactly does "stronger piston" mean?
I understand that the smaller piston will give you less rotating mass, however the longer stroke will increase your piston speed correct? This is also not great for high RPMs. Not that im planning to spin this thing to the moon either.
I guess what I'm looking for is what combo of bore x stroke is most reliable? Or what is preferred? Does it really even matter much?
I understand that the smaller piston will give you less rotating mass, however the longer stroke will increase your piston speed correct? This is also not great for high RPMs. Not that im planning to spin this thing to the moon either.
I guess what I'm looking for is what combo of bore x stroke is most reliable? Or what is preferred? Does it really even matter much?
#6
FormerVendor
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What exactly does "stronger piston" mean?
I understand that the smaller piston will give you less rotating mass, however the longer stroke will increase your piston speed correct? This is also not great for high RPMs. Not that im planning to spin this thing to the moon either.
I guess what I'm looking for is what combo of bore x stroke is most reliable? Or what is preferred? Does it really even matter much?
I understand that the smaller piston will give you less rotating mass, however the longer stroke will increase your piston speed correct? This is also not great for high RPMs. Not that im planning to spin this thing to the moon either.
I guess what I'm looking for is what combo of bore x stroke is most reliable? Or what is preferred? Does it really even matter much?
Cup engines are 4.155" bore x 3.3" stroke
Those engines teams are looking down to the 1/10 th. of a horsepower gain from every element. Cup engines rule is 358 ci, no rule on crankshaft size yet they use 3.3" stroke.
Heres what a "strong" piston looks like, 1.270" CH
you can't fit that dimension piston into a 1.050" compression height
Last edited by AES Racing; 10-05-2010 at 09:00 PM.
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#10
TECH Apprentice
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So best would be 4.125 bore X 4.000 stroke?
That way you can run better heads, bigger valves
Also stated that the larger bore will unshroud the values, fill the cylinders better, as well as allow more airflow?
What about the rotating mass...how is it with this setup...compared to others...
Any other examples...compared to this one...
That way you can run better heads, bigger valves
Also stated that the larger bore will unshroud the values, fill the cylinders better, as well as allow more airflow?
What about the rotating mass...how is it with this setup...compared to others...
Any other examples...compared to this one...
#12
LS1TECH Sponsor
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Big bore, short stroke will result in the most durable engine with respect to the bottom end.
Cylinder wall thickness should not be sacrificed to gain the last few cubes. 4.125 bore is not excessive with the proper block. Always stay within the recommended max bore size.
For 750hp, you do not need anything excessive & can do this with a well built engine on low boost.
Cylinder wall thickness should not be sacrificed to gain the last few cubes. 4.125 bore is not excessive with the proper block. Always stay within the recommended max bore size.
For 750hp, you do not need anything excessive & can do this with a well built engine on low boost.