Titanium : Usage in Engine Internals 1

[NakedTestMonkey]

I would like to get an idea of what I am facing by utilizing titanium material vs. conventional materials. Mainly the adverse conditions they bring up.

I would also like to hear your opinions as well.

The engine is a 4-cyl. 2.oL (86mm x 86mm) engine.

I plan to use titanium rods, and titanium wrist pins in order to reduce engine rotational weight.

Sorry if I sound like an idiot but I'm having to learn as I go here.

 

[ctmtwilliams]

Ti valves have been around for years.

 

[Majik]

SR20det eh... titanium rods and wrist pins are nice and have been around for atleast 25 years. Just remeber about those aluminum blocks and how much HP they hold.

 

[NakedTestMonkey]

The engine isn't going to require any block work, the power I will be making is relatively low. I am seeking response and a wide powerband.

My next hurdle is overcoming the engines tendency to lose it's rockers.

Thanks for the response, I am just trying to look at things from all angles rather than running into something a simple question could resolve.

 

[Majik]

are you trying to build a NA sr20? The rockers item is done with a set of greddy or other manufactur rocker stopers. unless you are trying to rev the snot out of the engine and are aproaching reengineering the valve train. A high rev boosted 4 cylinder is going to run into turbo issues on a wide powerband even with the GT series garrets. Finding one that won't choke that engine at high RPM and provide boost at low RPM is going to be difficult.

 

[EddyC]

Racers have been using lightened crankshafts and smaller flywheels in order to reduce the rotating weight. This would apply to the entire driveline as well since it all needs to accelerate (increase RPM) when you step on the gas.

 

[NickE]

here is a good thread discussing comparative benefits of Ti vs Steel... (although the good bits are in with the cabbage too)

thread90-90426

 

[Majik]

Hi nick.. great link one thing they mentioned is titanium wrist pins and no one had an answer to the coatings used. Casidiam coating is normally used in race car applications with titanium wrist pins. They work great.

http://www.casidiam.com/appn_3.htm

Also allows in short run applications for the bronze bushing to be removed from the rod if it's machined properly.

 

[R1100S]

Be careful with Ti rods. There are plenty out there so I don't what to scare you away, but be careful with the geometry. Rods need to be stiff. Ti is not stiff. Don't just copy the steel geometry with Ti.

 

[Deathscythe556]

Ti is a more molecularly abrasive material than steel so i would hesitate to use it anywhere near a bearing, especially a little end. the cheaper Ti parts will probably be more of a reverse finance than the more expensive stuff. I remember when titanium piston rings entered the scene and suddenly loads of people were having ring blow-by, piston slap and worn barrels because the technology was just not behind it. Titanium nitrided bearings, barrels, pistons, rings and bearings seems to be a good idea before going mental with the wallet. get rid of any lingering friction problems before throwing trick but dodgy parts into the mix.

 

[patprimmer]

As I remember, a bronze bush has been sometimes used to good effect as a bearing in the little end of steel rods

Regards

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