Thoughts on titanium rods.
10-26-2011, 08:01 PM
#1
Melting Slicks
Thread Starter
Thoughts on titanium rods.
Yes, It has been covered before but nothing recent.
So what are your thoughts on them? pros/cons?
My understanding is that besides being lightweight, they were required for bearing film pressures and crank balancing.
At what RPM, HP, or torque rating are they good for? Ive never seen anything stating they are rated for a certain HP level, but how will they hold up with boost and 800+ HP?
So what are your thoughts on them? pros/cons?
My understanding is that besides being lightweight, they were required for bearing film pressures and crank balancing.
At what RPM, HP, or torque rating are they good for? Ive never seen anything stating they are rated for a certain HP level, but how will they hold up with boost and 800+ HP?
10-26-2011, 11:41 PM
#2
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Here is a copy of a Hot Rod Magazine article on Titanium Rods from Feb. 2009:
Titanium
Got a huge wad of cash burning a hole in your wallet? Then you'll want to know that titanium rods offer the highest strength-to-mass ratio of them all. A well-designed titanium rod is about 20 percent lighter than a comparable steel rod. Titanium is the most abundant element in the earth's crust, but it must be alloyed with other metals before it has the properties needed for the manufacture of connecting rods. The most common alloy is called "Titanium 6-4" because it has 6 percent aluminum and 4 percent vanadium to improve machineability.
Like steel and aluminum rods, titanium rods can be forged or cut from a billet. Given a choice, titanium rods are most durable when manufactured by the forging process. This is because the grain size of even the best aerospace grade titanium is less than steel. In a Richter-esque grain-sizing scale where a 6 rating is twice as tight as a 5 rating, titanium rates between 5 and 6 while high-carbon steel is far more cohesive, rating as high as a 9. To offset the possible negative impact on strength, a fully machined forged titanium rod is the best type thanks to the improved grain structure around the big end versus a cut-out true billet titanium rod.
Though raw titanium costs five times as much as raw carbon steel, the average retail cost of a set of titanium rods is "only" about twice that of steel. The increased consumer cost reflects the fact that titanium becomes "gummy" when machined and requires specialized tooling and slower feed rates. Titanium expands at about the same rate as steel and is resistant to work hardening, so you could run 'em in your street car with no problems as long as your wife never sees the credit card bill. So where do titanium rods really shine? In any all-out racing effort where an approximate 15-percent reduction in ultimate tensile strength is an acceptable trade-off for an approximate 20-percent reduction in connecting rod weight. As for ultimate power capacity, know that they're used in everything from 9,000-rpm NASCAR motors to a handful of 6,000hp Top Fuel motors (though most teams use aluminum). With the right communication between you and the manufacturer, they'll handle anything you can throw at 'em. Just be sure not to scratch them! Titanium is very "notch sensitive." Small surface imperfections caused by rough handling must be polished immediately, or they can grow quickly.
Read more: http://www.hotrod.com/techfaq/hrdp_0...nium_rods.html
Bill
Titanium
Got a huge wad of cash burning a hole in your wallet? Then you'll want to know that titanium rods offer the highest strength-to-mass ratio of them all. A well-designed titanium rod is about 20 percent lighter than a comparable steel rod. Titanium is the most abundant element in the earth's crust, but it must be alloyed with other metals before it has the properties needed for the manufacture of connecting rods. The most common alloy is called "Titanium 6-4" because it has 6 percent aluminum and 4 percent vanadium to improve machineability.
Like steel and aluminum rods, titanium rods can be forged or cut from a billet. Given a choice, titanium rods are most durable when manufactured by the forging process. This is because the grain size of even the best aerospace grade titanium is less than steel. In a Richter-esque grain-sizing scale where a 6 rating is twice as tight as a 5 rating, titanium rates between 5 and 6 while high-carbon steel is far more cohesive, rating as high as a 9. To offset the possible negative impact on strength, a fully machined forged titanium rod is the best type thanks to the improved grain structure around the big end versus a cut-out true billet titanium rod.
Though raw titanium costs five times as much as raw carbon steel, the average retail cost of a set of titanium rods is "only" about twice that of steel. The increased consumer cost reflects the fact that titanium becomes "gummy" when machined and requires specialized tooling and slower feed rates. Titanium expands at about the same rate as steel and is resistant to work hardening, so you could run 'em in your street car with no problems as long as your wife never sees the credit card bill. So where do titanium rods really shine? In any all-out racing effort where an approximate 15-percent reduction in ultimate tensile strength is an acceptable trade-off for an approximate 20-percent reduction in connecting rod weight. As for ultimate power capacity, know that they're used in everything from 9,000-rpm NASCAR motors to a handful of 6,000hp Top Fuel motors (though most teams use aluminum). With the right communication between you and the manufacturer, they'll handle anything you can throw at 'em. Just be sure not to scratch them! Titanium is very "notch sensitive." Small surface imperfections caused by rough handling must be polished immediately, or they can grow quickly.
Read more: http://www.hotrod.com/techfaq/hrdp_0...nium_rods.html
Bill
10-27-2011, 07:45 PM
#4
Melting Slicks
Thread Starter
Pretty interesting article. I was debating if it was worth it to upgrade to forged rods in my new build.
Does anyone know the compostion of the titanuim used, or if they are forged ro cast?
Does anyone know the compostion of the titanuim used, or if they are forged ro cast?
10-27-2011, 07:49 PM
#5
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The LS7 rods are forged.
Bill
Bill
