[bumpin96monte!]

So the two choices that seem to be available are either the steel or titanium, it seems like all the engine books I've been reading (granted these are usually v-8 biased) seem to say that while titanium retainers do help, they only reccomend them for track only cars, where you will be regularly pulling off the valvecovers because their reasoning is that the titanium retainers are more prone to cracking and subsequently coming apart than their steel counterparts. They say on a street engine just to run steel becuase the chance for cracking is lessened and since you don't pull your valve covers that often, its one less thing to worry about. Is there any truth behind this?

 

[JasonGS]

I dunno, but that may warrant me pulling my valve covers off.

 

[smellbird]

I know titanium is very brittle, especially compared to steel. But in order for it to get stressed enough to break you'd have to be running some extreme temps and putting extreme pressure on them. So there is truth behind it, but it's a misleading truth
The only reason I can think to go with steel is to save a few bucks, the titanium might help rev a little faster.

 

[Rogue]

Titanium alloys are one of the strongest materials on the planet. The combination of strength and lightweight allows your valvetrain to rev faster and higher.

Titanium and its alloys have attractive engineering properties. They are about 40% lighter than Steel and 60% heavier than Aluminum with a density of .163 lbs/in3. The combination of moderate weight and high strength gives Titanium alloys the highest strength to weight ratios of any structural metal.

Titanium is used in diverse applications - from aircraft parts to surgical implants, and as hardware for marine and chemical equipment - wherever high strength to weight ratios, high temperature stability and good corrosion resistance to salt water and chemicals is required.

Titanium and its alloys have flat stress strain curves, and when properly machined, can produce an excellent surface finish due to its unique chip formation characteristics. For best results, re-sharpen tools frequently; use proper tool angles and adequate coolants, directed closely to the point of contact. Slow speeds and heavy feeds are recommended.

Commercially Pure (CP) Grade 2 is 99% Titanium, alloyed with minimal contents (0.20% or less of each) of iron, oxygen, carbon, nitrogen, hydrogen, and less than 0.4% residual elements.

A read on titanium and its uses in engines can be found here: http://www.materials-edge.net/html/print.php?sid=100

Titanium has many advantages. Titanium has these key properties:


Lightweight and Strong
Excellent fatigue strength (twice that of 4130 steel)
Excellent elongation (ductility). Ductile metals are pliable and easily worked, and can be drawn, shaped and formed without cracking or breaking
Excellent corrosion resistance

 

[Overclock This]

What are the ZZP milled retainers made from?

I'm going to be using them with my S3 cam, 130# valve springs.
They'll be ok?

 

[Overclock This]

Anybody have an answer?

 

[spd98]

While this may be true in general for titanium there are MANY different alloys. Not as many as steel but alot. I would guess theier of the 2/2.5 range but you would need to know that to be sure of the properties. Some of the manganese alloys get very very hard and very brittle. So basically you need more info to be sure although I would guess comp has selected the correct alloy for the aplication. I would email comp and ask them. They are just TI ls1 retainers.

 

[bumpin96monte!]

It seems as though no one has actually had them crack on our cars that I've seen, thats what I was wondering about, but since no one has posted, I guess they're okay to use for the street, thanks for the help.