boaring out the cylinders
american_muscle
02-05-2006, 03:35 AM
A while back i heard something about boaring out the cylinders in your engine for a massive power gain. Is this an actual mod....and if so, how much hp does it get? I might be off on this and be thinking of something else, but i'm 90% sure that it was called boaring out the cylinders.
MagicRat
02-05-2006, 08:24 AM
There is a tiny power increase, but not a 'massive' one.
Boring the cylinder is usually done when an engine is rebuilt and new pistons and rings are installed.
A small amount of metal is removed from the cylinder wall. This removes all of the wear marks caused by piston travel and makes the cylinder perfectly round and straight again.
The amount of metal removed is small, often .030 of an inch is enough.
This does add displacement to an engine, but not much.
A 351 cid V8 when bored .030 will actually be about 356 cid.
The most an engine can be bored to is .060 over stock. Some engines can take .080 over, depending on the design.
This very small increase in displacement will not give a 'massive' increase in power. A very accurate dyno test might be able to measure the power gain, but other factors, like the increased friction of new engine parts will steal all the gains made from the displacement increase.
Finally, if you have an engine that is COMPLETELY worn out, a boring and rebuilding the engine will give lots more power, but that is because you are only restoring all teh power that was lost to extreme engine wear.
Boring the cylinder is usually done when an engine is rebuilt and new pistons and rings are installed.
A small amount of metal is removed from the cylinder wall. This removes all of the wear marks caused by piston travel and makes the cylinder perfectly round and straight again.
The amount of metal removed is small, often .030 of an inch is enough.
This does add displacement to an engine, but not much.
A 351 cid V8 when bored .030 will actually be about 356 cid.
The most an engine can be bored to is .060 over stock. Some engines can take .080 over, depending on the design.
This very small increase in displacement will not give a 'massive' increase in power. A very accurate dyno test might be able to measure the power gain, but other factors, like the increased friction of new engine parts will steal all the gains made from the displacement increase.
Finally, if you have an engine that is COMPLETELY worn out, a boring and rebuilding the engine will give lots more power, but that is because you are only restoring all teh power that was lost to extreme engine wear.
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