jlobbia
RCTalk Racer
What is the difference between big block and small block engines? I have been in nitro for quite a while but never really got a clear answer. Thanks.
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The size of the block. 
Jeez, I'm an idiot. Same as car engines, big block has a longer piston stroke and more low end torque. Small block is a shorter stroke with more RPMs on the high end. Different gear ratios for maximum performance.
Jeez, I'm an idiot. Same as car engines, big block has a longer piston stroke and more low end torque. Small block is a shorter stroke with more RPMs on the high end. Different gear ratios for maximum performance.
The crank case is longer and wider physically. Carb is typically larger on a big block as is the exhaust port.
This is an old photo I had of a Omega 21 big block (top) and an OS 18 small block (bottom):
This is an old photo I had of a Omega 21 big block (top) and an OS 18 small block (bottom):
jlobbia
RCTalk Racer
- Thread starter
- #4
Is there a point in size where it's defined as a big block? Like everything after .19 is a bb, and everything before is a sb?The crank case is longer and wider physically. Carb is typically larger on a big block as is the exhaust port.
This is an old photo I had of a Omega 21 big block (top) and an OS 18 small block (bottom):
D3MON
Hardcore RCTalk User
Typically
.12 (2.0CC)-.20 (3.3CC) is small block
.21 (3.5cc) and up to .36 (5.9CC) is big block
.37 and up is kind of a specialty category, mounting is typically different than the standard sized for big blocks.
as usual in RC there are exceptions, like the O.S. .21TM, its a big block internals with a small block case.
Picco .26max and a few other ones that i can't recall, are was what is called a "Mid-Block", small"er" block, case with big block internals.
.12 (2.0CC)-.20 (3.3CC) is small block
.21 (3.5cc) and up to .36 (5.9CC) is big block
.37 and up is kind of a specialty category, mounting is typically different than the standard sized for big blocks.
as usual in RC there are exceptions, like the O.S. .21TM, its a big block internals with a small block case.
Picco .26max and a few other ones that i can't recall, are was what is called a "Mid-Block", small"er" block, case with big block internals.
