Titanium Tail Pipes
 

I would like to know if anyone has considered using titanium instead of stainless tail pipes.

The weight savings should be significant...Other than price,I wonder what disadvantage there may be ?

If the savings was 15-40 lbs per tail pipe, how much would you pay?

With a Wt. saving of 40# x 4 tails, that would cause one to seriously listen to your proposal !

We would like to know what you are thinking .

Do you have aluminum blocks yet? They would be cheaper and save more weight.

CcanDo,
A weight savings of 140#, at the height and aft position of your tails would have a positive effect on the CG and longitudinal center of balance.

Bob

No, we don't have aluminum blocks . Aluminum blocks for the marine application makes me a little nervous. Corrosion,oxidation,thermal shock and align bore would be the primary concerns.Internal coating would address some concern.

In fact, the graphite/carbon steel block casting is said to weigh somewhere between aluminum and cast iron,plus includes other benifits.

Titanium tail pipes may not be feasible. However,on boats with limited bilge length,overhung load of mufflers, heavier drives, added stand off boxes,transom reinforcement and etc.,
CG becomes a problem. Therefore ,while total weight is an issue it is more manageable than CG in some situations. Further,if one could effect both CG and Wt. by simply changing tail pipe material it may be feasible. An example would be the boat that doesn't quite go on plane because the transom/boat gained Wt..Now what do we do ? If the option were available to bolt on a 160# of Wt. saving while shifting the CG it may be worth considering,especialy for some boats.

It has been said Russia has an an abundance of raw Titanium. Therefore, as globalization evolves, perhaps someone here has access to commodity pricing for Titanium tube.

Then, after sticker shock, the theory of Titanium would have to be tested and proven. However,if the pipes were without turns or bends it should be somewhat straight forward.

What is your response to that ? Is there a need ? People commit a lot of resources to gain speed and handling that 160# Wt. savings would provide.

A practical alternative, used a the highest level of motorsport including F-1, is thinwall Inconel alloy. The weight savings are significant and the material is proven and durable. The big plus with Inconel is the people, materials, and development are already in place to make this happen.

Attached is a photo of a set I have from the Honda F-1 program.

rmbuilder

Good hearing from you !

Have we worked together since the crank to rod ratio thread ? That was fun and now more people are talking about idle torque,dock manners,durability and generally having more fun. Your articulate information made a significant contribution. Also,I see people throwing Gold Stars for other things you have been doing for them.

As for the influence Titanium may have,it sounds like you and I are on the same page. Do you have time to expound ? Please !

rmbuilder

Sorry, you were posting while I was in a meeting...then the "go button" was punched....You had already posted.

Do you have anything with Wt. factors for the various materials ?

For asthetics, is there a way of creating a little more Bling on Inconel ?

Also, should the muffler be designed for attachment to the header collector,then attach the tail pipe to the muffler ? The purpose of that method would be to better offer protection for the transom,header stress,CG and etc.

CMI might be a good source of info on lighter metals for marine tail pipes. The water jacketed design could be a challenge for some welded metals.

Check this website. www.titaniumengineers.com
They are also in TX. Tubing up to 10.5" OD with wall thickness as little as .125"

Inconel® refers to a family of trademarked high strength austenitic nickel-chromium-iron alloys that have exceptional anti-corrosion and heat-resistance properties. These alloys contain high levels of nickel and can be thought of as super-stainless steels. Inconel alloys are used for a variety of extreme applications including navy boat exhaust ducts, submarine propulsion motors, undersea cable sheathing, heat exchanger tubing and gas turbine shroud rings.

For many years, Inconel has been used for Formula One and Champ Car exhaust systems. More recently, several Winston Cup racing teams have utilized Inconel for producing ultra-light, high-durability exhaust headers.

Burns Stainless recommends Inconel 625 alloy for exhaust systems due to its excellent strength, corrosion resistance and fabricability. This alloy also exhibits high creep and rupture strength; outstanding fatigue and thermal-fatigue strength; as well as excellent weldability (though the guy welding it might have a different opinion!). Inconel 625 contains molybdenum and columbium, which stiffens and strengthens the nickel-chromium matrix without precipitation hardening treatments. Some hardening however does occur when heated to intermediate temperatures (1200 F to 1600 F) increasing room temperature strength. Also, this alloy retains over 75% of its room temperature strength at 1200 F. This alloy is available in a wide variety of forms including tubing, sheet, bar, plates and castings. Burns Stainless typically stocks welded and drawn Inconel 625 tubing. The tubing specification is SAE AMS 5581, Nickel Alloy, Corrosion and Heat Resistant, Seamless or Welded Tubing.

Inconel 625 can be welded using conventional stainless steel TIG welding techniques. Inconel Filler Metal 625 rod is used to weld Inconel to Inconel as well as to dissimilar metals including stainless steel. Inconel weldments are high strength and are highly resistant to corrosion and oxidation. Many welders describe that welding Inconel as "dirty". In other words, the weld pool appears to be under a "skin" and is not well defined. In addition, the weld pool is somewhat "sluggish" as compared with steel or stainless steel. These characteristics tend to result in a "coarse" appearing weldment as compared to stainless steel. Welding Inconel is not necessarily more difficult to weld than stainless, just different. By following the welding procedures outlined in the header construction tips article, successful welds with Inconel 625 are possible.


Credit Burns Stainless

As for the bling:

My headers are used up, but it doesn't get much better than this

RMB,
Is Inconel lighter the the standard SS that is used in marine tail pipes today? or are they less weight because you are able to use a thinner wall tubing? Both? Amount?

Ti tubing on E-bay from Shapiro's (I have bought Ti from them and titanium joe for other projects before)-110$ for 36" piece of 4.5" dia .050 wall type 2 grade 3,not really that exspensive,Smitty
http://cgi.ebay.com/TITANIUM-TUBE-4-...QQcmdZViewItem

Inconel 625 properties:

CcanDo,

Good hearing from you also!

Ben,

I do not have the materials density sheet at hand now, however a great deal of the weight saving is in the wall thickness. The headers I have are BAR Honda race distance versions circa 2002 and I believe the wall thickness is .030", in qualifying trim they were .015" (not a misprint). By doing the headers and tails you can easily pull 40+# from each engine.
They won't be cheap, but cheaper, lighter and more durable than TI.

These folks have budgets exceeding 600 +M annually and speak of weight in grams, if there was a better option out there they would be using it.

Bob

I am guessing those would cost about 10k for a set?


Didnt Dave Scott have a set on one of his race boats

Bob ,someone here suggested that I ask why you are called "rmbuilder". Does it have anything to do with Rehr-Morrison Engines ?

Your headers don't looked used up to me, in fact, they look new... Very nice. What material are they and how did you get them to look like they are in the picture?

I wish we knew how frequency ring/harmonics compare between SS, Inconel and Titanium. One of those materials must be superior for control of exhaust noise DB rating.

I'd like to suggest that we first work on straight tail pipes, then a muffler that installs between the tail pipe and header, and then perhaps on headers. That should not pledgerize anyone because,to my knowledge no one is doing anything with Inconel or Titanium, in this application.

I'm confused by mufflers and noise laws and others must be also. Regardlous, I would prefer to see the Wt. removed from outside the transom and located at the header collector. Surely, that is a do-able.

Who is interested in chairing that coalition ? There just might be some opportunity.

Rob,

Probably all of that and then some. The big plus in going with Jack Burns is not only the materials and workmanship ( and weight savings), he is absolutely at the top of the game in exhaust science from F-1/Cup/ALMS/LeMans/NHRA. The benefit is in the end result you will be optimizing both power and TQ placement. I have a report on a set of marine headers he did, here is an excerpt:

"We designed and made improved headers for a 562 cubic inch
Chevrolet jet drag boat engine that produces 950 bhp," reports
Jack Burns. "This engine breathes through a tunnel-ram manifold
fitted with a pair of four-barrel Holley carburettors. The engineering
exercise required designing, constructing and tuning the exhaust
to maximize the power curve in a narrow band: between 6600 and
6700 rpm.
"We utilized our DesignSYS software and built the header
shown in the accompanying illustration. We utilized our adjustable
BTEC collector system. The baseline headers were good-quality
commercially available racing units.
"On a SuperFlow dyno, our system improved peak torque by
24 ft.lb. and increased maximum power by 14 bhp. But the target
was to increase power in the 6600-6700 rpm range, which we
increased by 21.5 bhp. Overall, the powerband broadened during
the dyno test runs from 5500 thru 7500 rpms, with an average
torque increase of 16 ft.lb. and average power increase of 20 bhp
compared to the baseline."

Bob

Titanium Tail Pipes
 

This thread has stalled because the usual page bar seems to be missing....I did email OSO and suggest review,however maybe this will get it going.

Thats a pretty good increase in just header design over a already race set of headers,Bob is the Jack Burns the one from Burns Stainless exhaust ? That name seemed failmure from the PRI show.

http://www.burnsstainless.com/

Ck out this on the Inconel tubing
http://www.honda-tech.com/zerothread?id=1378601

Also I got to thinking , on the tail pipes. If you do some searching, theirs a lot of the sport bike exhaust companys that make titanium headers fro the if you could get one of them , I be they could make a set more reasonable than someone that makes them for F1.


might find some name brands
http://www.hondamarketplace.com/zerothread?id=1944162

http://www.nengun.com/js-racing/tita...exhaust-system

I had a friend with a racebike that had custom swingarm and plastics therefore had to have a pipe built for it.. He had a local place here in tulsa weld a full titanium system up and it cost him around $600..which is about dead even with the cost of a NEW ti system. His had about athousand different welds in it, no bends at all.. not sure why, thats just how they had it done..

Waterboy 222 , I went to flight school in Tulsa...Neat area.

What type of fab shop did your friends suspension ? Possibly those people can offer food for thought,that is,if you were to have time to visit with them.

Ti and Inco 625 are both very weldable by those competent and knowledgable in their respective properties. The trick with the Ti is in choosing the proper alloy Ti as it is with choosing the right alloy of Inconel. There are several alloys of both that are designed for specific uses. The Inconel will very likely give better long-term salt-water durability, which might help with the offset of greater cost over the stainless currently out there. The Inconel does have a greater density than the stainless, and greater than most other materials you might use in this application.

Density of Inco 625=8.44g/cm3
Density of Titanium=4.5g/cm3
Density of 304 SS=8.03g/cm3

Both the Titanium and the Inconel polish up nicely and hold their shine. Both have pretty good heat stability. I'm a little out of touch with the current markets for tubing of either material, but there are lots of sources for both, and both are readily available in numerous OD x wall thicknesses. They won't be cheap.