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

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.