Compacted Graphite Blocks

[CcanDo]

:),The application is Marine, fresh water cooled. What comparisons could be made between the Compacted Graphite block, cast and aluminum ?

[Awesome Bill]

Compacted Graphite is very dense and mostly used in very high hp applications and won't really make any more power than cast but most likely would last longer in salt water. Aluminum pretty much the same thing. Some say it makes less power but I have never seen that. If the engine runs 20° cooler because of the block, I would tell them to change out your thermo. We dyno everything @ 160 for gas and 180 for alky. Never seen the aluminum block make less unless I ran it before 180.

[CcanDo]

Compacted Graphite is very dense and mostly used in very high hp applications and won't really make any more power than cast but most likely would last longer in salt water. Aluminum pretty much the same thing. Some say it makes less power but I have never seen that. If the engine runs 20° cooler because of the block, I would tell them to change out your thermo. We dyno everything @ 160 for gas and 180 for alky. Never seen the aluminum block make less unless I ran it before 180.

Thanks Bill, The CG Block is a new twist to many,especially marine users. Therefore, IMHO, it may be worth definate consideration. Residual value to a later owner carries some degree of reassurance and/or perhaps bragging rights. I realize machining is or can be a bit of a problem. In fact, what is the safest approach to "freshening" the block if one doesn't have CG machining tools ? Beyond that concern, it seems the modern day OEM's are taking a hard look at using Compacted Graphite.

[Awesome Bill]

Speeds and feeds are the key with sharp cutters. Other than that, nothing. I usually run a little more piston to wall with the compacted applications! Especially with Marine. I would say the Marine Turbo application would be a very good choice for the cg block. Salt water tends to do less damage with proper care on any block. when you leave it sit for years without service is what kills the metal in the standard blocks. Heads take the most beating!

[donaldjeo12]

n 1949, a now well-known material called ductile iron was patented. At the same time, a lesser-known material called Compacted Graphite Iron (CGI) was also patented, though it was just considered a curiosity at the time.

While ductile iron became a manufacturing staple, CGI never was seriously utilized despite possessing some very interesting properties. While not quite as strong as ductile iron, CGI is 75 percent stronger and up to 75 percent stiffer than gray iron.

The thermal and damping characteristics of CGI are midway between ductile and gray iron. It is five times more fatigue resistant than aluminum at elevated temperatures, and twice as resistant to metal fatigue as gray iron.

The nodularity and tensile strength of the material also increases as wall-section decreases.

These properties have most recently been found to make CGI ideally suited for engine manufacturing, where lighter and stronger materials are needed which can absorb more power.

An assembled automotive engine can be made nine percent lighter with CGI. The engine block weight alone can be reduced by 22 percent. This corresponds to a 15 percent reduction in length and a five percent reduction in height and width.

[Awesome Bill]

n 1949, a now well-known material called ductile iron was patented. At the same time, a lesser-known material called Compacted Graphite Iron (CGI) was also patented, though it was just considered a curiosity at the time.

While ductile iron became a manufacturing staple, CGI never was seriously utilized despite possessing some very interesting properties. While not quite as strong as ductile iron, CGI is 75 percent stronger and up to 75 percent stiffer than gray iron.

The thermal and damping characteristics of CGI are midway between ductile and gray iron. It is five times more fatigue resistant than aluminum at elevated temperatures, and twice as resistant to metal fatigue as gray iron.

The nodularity and tensile strength of the material also increases as wall-section decreases.

These properties have most recently been found to make CGI ideally suited for engine manufacturing, where lighter and stronger materials are needed which can absorb more power.

An assembled automotive engine can be made nine percent lighter with CGI. The engine block weight alone can be reduced by 22 percent. This corresponds to a 15 percent reduction in length and a five percent reduction in height and width.

Sounds very good to me. You have been doing your homework! AAAA++++