WORLDS different between a thermite reaction and what you'll see in applications... really, worlds different.
You don't use any pure metal in a high stress environment, you use an alloy.

Forged and/or billet Ti rods aren't a bad way to go, I'd looooove those someday

Offtopicish time:

When you get aluminum bits down to a sufficiently fine size, you'd have enough actual Al to be useful in a rX. This in turn has the free Al particles able to react with the Fe and create the highly exothermic process given sufficient oxygen and initial energy (friction heat). I don't hear of Al engine parts spontaneously combusting a lot. There are turbochargers out there that have Aluminum compressors, and some jet engines as well (in the lower temp areas so it doesn't melt first)

I don't want to stray offtopic by posting rebuttals to the aluminum armor idea, it can get quite lengthy. However yes, ANY metal on fire is a real bitch to put out and I wouldn't want to be near it. And anything that has Aluminum armor, I wouldn't want to be in just because it's not exactly the toughest material out there for withstanding a lot of bullets or impacts. (RPG would probably punch through the Al armor getting the explosion to hit the inside)

 

People who are bashing titanium rods:

A) are too poor to ever afford a set, therefore must bash them to justify going with cheap ones

B) Don't understand metallurgy or the properties of titanium


I don't see how someone can bash a good set of titanium rods?!? They are expensive, but they are the best material for the job in an ideal world.

Titanium is probably one of my favorite materials.. I just can wait till we start getting titanium springs to become more commonplace. Much higher fatigue life and lighter for the same spring rate!!! Just too bad it costs so much.

 

I believe a key component to understanding why titanium makes great engine parts is that you are not using pure titanium as a connecting rod. You are using an alloy. The composition of an alloy is what makes or breaks a part. The companies who produce titanium parts know what they are doing and know what alloy is going to stand up to the temperatures/stresses of the part they are designing. Can you get by in 99.9999% of most engine builds with something else? Yes! Are there times when titanium is a poor choice? Yes!
But these things don't change the fact that titanium is still a great metal for many applications.

 

Yup getting the right alloy is key!

although Grade 5 (Ti 6-4) will get you a long way...

 

Titanium rods themselves aren't going to break. But they are a poor choice for some applications. Theres a racing class using I believe buick engines, one of the requirements is stock cast crankshaft, no forged peices. The engine builders for this class use aluminum rods in the high power engines because the aluminum absorbs the shock and saves the crankshaft. Since the crankshafts aren't produced anymore replacing a crankshaft becomes expensive, whilst replacing connecting rods is relatively cheap. Granted this is very much a corner case and not the norm but there are other cases similar to it. Imagine using titanium rods with a cast crank in a 2 bolt block. You'd spin a bearing every race. Plus, after a couple seasons when it comes time to polish your crank and resize the big end of the rods, its hell to find someone with the equipment to work titanium.

 

ace! got any pics of the builds or engines????

(and just to keep it on topic) any pics of the rods?????

Chris.

 

Chris,

Some parts are here including the rods:
http://www.pistonheads.co.uk/gassing...65605&f=69&h=0.

Heads are away being coated, pistons are on order, the plenums having the coolers fitted. I expect Harry's to come together in about 6 weeks

Boosted.

 

that looks amazing! what turbo setup is going in the manarno? how about for the TR8? how come you have gone for 427 over stroked LS1's???

think you should buy an ultima and show everyone how to do it!

thanks (a very very jealous) Chris.

PS. need any weekend a helper????

 

I've seen a titanium crankshaft. It's a thing of beauty. I have never gotten to touch the crankshaft though but the rods themselves... I held them in my hands and it was like holding the ark of the covenant. They were so light and yet the metal had a strange feel to it, its like the difference between drinking patron and drinking jose cuervo. They're both the same thing yet they feel completely different.

 

Aluminum sheets etc. etc. doesn't burn, but aluminum powder, along with any other powder, has the capacity to explode when ignited. Even grains can do this, that's what a silo explosion is

 

Aluminum sheets can burn, thats why you need a special welder to weld aluminum. Coincidentally so can iron, thats how an acetylene cutting torch works.

 

Genesis, the cranks are forged by callies. Rods are titanium.

Chris, don't need an ultima. A good TR8 ought to see one off plus it has boot space. Stevie T seems to better their figures already. Just goes to show what good work privateers can do.

Boosted.

 

My little brother and I use to make Thermite! Fun stuff.

 

believe it or not Eagle now also sells Ti rods but since it's late and I am at Home I don't kow the price right offhand.

 

another thing to consider is that titanium is very notch sensative, tiny surface scratches can lead to stress concentrations which promote cracks and rod failure.

 

Ti is also not friendly to being rubbed on. Ti springs are coated so the retainers will not beat them up.

People who say aluminum rods are not safe for the street are working on very old information. Get rods that are made of 7075 T6 and put an oil temp gauge in the car. They do not like very high oil temps. Not really an issue with street engine.

Stay away from 2014 rods. They will work harden and break with street use.

 

Special welder to weld aluminum? You can MIG weld aluminum just like you can MIG weld steel using the correct gas and wire. You can also TIG aluminum just as you would steel.

 

Lienus,
Could you please elaborate on the manufacturer and application that you had first hand involvement with a Ti crankshaft?

Thanks in advance

 

You can't use innercore to weld aluminum, you can't use a stick welder for the most part to weld aluminum either. You have to spend a bit more and get a welder with some form of controlled gas displacement systems rather than the garbage that is innercore.

 

I can't really. I was brought in well after the engine was built, I wasn't even directly involved in it at the time either it was just getting a new set of pistons so the rods were out and I had the opportunity to see the insides. The engine turns about 8000 rpm and makes about 800 horsepower and is under 400 cubes. I am being put in a position where I likely will end up maintaining this engine and the car it belongs in however as of right now it's not my project. AFAIK the manufacturer of the crank and rods is no longer around. The engine is probably around 5 years old now and the only issues it has had are thin port walls on the heads and a poor carburetor tune costing the engine a couple of pistons.