3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

Titanium can't take the heat?

Thread Tools
 
Search this Thread
 
Old 01-29-04, 02:30 PM
  #26  
Senior Member

 
ForceFed's Avatar
 
Join Date: Feb 2001
Location: Charlotte, N.C.
Posts: 445
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by Matt Hey
A Stainless Steel downpipe would hold in the heat better than a Titanium downpipe (= cooler underhood temps). 321 SS or Inconel (best) is even better at holding in the heat, is more heat resistant, and stronger than 304 SS which most RX-7 downpipes are made from.
Precisely the point i was going to make until you beat me to it The SS DP does a much better job of getting the heat *out* the exhaust than Ti would. A Ti DP would allow more heat to permeate into the engine bay.

Darril
Old 01-29-04, 03:10 PM
  #27  
Ozone Depleter

 
teamstealth's Avatar
 
Join Date: Jul 2002
Location: StL
Posts: 1,610
Likes: 0
Received 0 Likes on 0 Posts
Just out of curiosity...how heavy is Inconel compared to SS and Ti?
Old 01-29-04, 03:13 PM
  #28  
Rotary Enthusiast

 
Louis M's Avatar
 
Join Date: Aug 2002
Location: RX7 Heaven
Posts: 1,090
Likes: 0
Received 0 Likes on 0 Posts
Originally posted by rfreeman27
Exactly. If you are so concerned about it, there are other, more effective ways of saving some weight.
like situps... -> $0.00
Old 01-29-04, 03:56 PM
  #29  
fart on a friends head!!!

 
rotorbrain's Avatar
 
Join Date: Mar 2002
Location: sheppard AFB, TX
Posts: 4,104
Likes: 0
Received 1 Like on 1 Post
burns stainless quotes that titanium shouldnt be used on rotary exhaust systems. id say the only real bad place is close to the turbo where a lot of heat is found. so, downpipes and headers are a "no,no". they also say that stainless isnt considered "good enough" to use on rotaries. that may be why a lot of stainless headers crack. the metal they recommend to use is inconel. . . try getting a good deal on that!!!!

paul
Old 01-29-04, 03:57 PM
  #30  
Moderator

iTrader: (7)
 
dgeesaman's Avatar
 
Join Date: May 2002
Location: Fort Kickass
Posts: 12,302
Received 16 Likes on 15 Posts
Originally posted by teamstealth
Just out of curiosity...how heavy is Inconel compared to SS and Ti?
Strength and weight similar to SS. Thermal expansion slightly less than SS.

Dave
Old 01-29-04, 05:35 PM
  #31  
PV = nRT

 
clayne's Avatar
 
Join Date: Jan 2003
Location: New Zealand (was California)
Posts: 2,250
Likes: 0
Received 0 Likes on 0 Posts
Cost greatly higher!
Old 01-29-04, 09:50 PM
  #32  
Rotary Enthusiast

iTrader: (2)
 
johnchabin's Avatar
 
Join Date: Feb 2002
Location: Centennial, Colorado
Posts: 1,053
Received 6 Likes on 6 Posts
Originally posted by rynberg
A SS downpipe only weighs 7 lbs. Why spend so much more money to save another 3 lbs? What a waste of cash.
Originally posted by dgeesaman
For me, I'll save weight by taking a dump before every time I race and save $600. That's like $300/turd.
Or $200/lb!
Old 01-31-04, 02:20 PM
  #33  
DoO user

 
Elevation7's Avatar
 
Join Date: Feb 2001
Location: Almost but not quite, way down South!
Posts: 177
Likes: 0
Received 0 Likes on 0 Posts
They used Titanium on the SR-71 for years and it was exposed to 1000 degrees worth of heat. I'd argue differently.

SS is cheaper and easier to work with though.

If you're looking for something good to make an exhaust system out of inconel aka basic SS is still a good choice and it's much cheaper.

SS is more corrosion resistant than most metals, and also has a low coeffecient expansion.

They use SS on all kinds of exhaust systems, so he's probably right.


You could also look at Nickel-steel alloy. It shares a lot of the properties of SS and titanium but has the added advantage of thermal shock resistance. They use them all over in turbine engines. Imagine being in Alaska say it's -60 below and you go to some hundreds of degrees in a matter of seconds.

However, I've never heard of such a thing in an exhaust set-up, other than stated above. Again cost will be an issue.

Last edited by Elevation7; 01-31-04 at 02:28 PM.
Old 02-13-04, 01:17 PM
  #34  
Senior Member

 
skim41's Avatar
 
Join Date: May 2003
Location: netherlands
Posts: 526
Likes: 0
Received 0 Likes on 0 Posts
Titanium gets its strength a 500+ degrees celsius. And of course is lighter and stronger dan normal stainless stell. You dont want to use both of them because they dont take up the heat as much as normal carbon steel does.
Old 02-13-04, 05:43 PM
  #35  
fart on a friends head!!!

 
rotorbrain's Avatar
 
Join Date: Mar 2002
Location: sheppard AFB, TX
Posts: 4,104
Likes: 0
Received 1 Like on 1 Post
Originally posted by Elevation7
They used Titanium on the SR-71 for years and it was exposed to 1000 degrees worth of heat. I'd argue differently.

SS is cheaper and easier to work with though.

If you're looking for something good to make an exhaust system out of inconel aka basic SS is still a good choice and it's much cheaper.

SS is more corrosion resistant than most metals, and also has a low coeffecient expansion.

They use SS on all kinds of exhaust systems, so he's probably right.


You could also look at Nickel-steel alloy. It shares a lot of the properties of SS and titanium but has the added advantage of thermal shock resistance. They use them all over in turbine engines. Imagine being in Alaska say it's -60 below and you go to some hundreds of degrees in a matter of seconds.

However, I've never heard of such a thing in an exhaust set-up, other than stated above. Again cost will be an issue.
inconel isnt stainless. . . and its waaaaaaaaay more expensive!!!!

paul
Old 02-13-04, 06:46 PM
  #36  
Speed Mach Go Go Go

iTrader: (2)
 
GoRacer's Avatar
 
Join Date: Oct 2001
Location: My 350Z Roadster kicks my RX7's butt
Posts: 4,772
Likes: 0
Received 2 Likes on 2 Posts
Inconel is part nickel. I inquired about both Inconel and Titanium with Burns and my bro-in-laws friend that makes custom cars with titanium. When my engine is in, i'll be making titanium parts (strut bars, toe liks, etc). Anyhow, Inconel is supposed to be like 3x the weight and the price. You better off getting a quality SS DP (with hanger) and 2k degree heat coating (before mounting). Inconel would be a perfect replacement for the turbo manifold ...no more f*'n crakcs!
Old 02-13-04, 07:37 PM
  #37  
fart on a friends head!!!

 
rotorbrain's Avatar
 
Join Date: Mar 2002
Location: sheppard AFB, TX
Posts: 4,104
Likes: 0
Received 1 Like on 1 Post
ss after the turbo is fine in my book. . . its at the header that it MIGHT be a problem. people have been making ss tubular headers for a while. . . i dont think its worth the money to have them made out of inconel.

paul
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Turblown
Vendor Classifieds
12
10-17-20 03:25 PM



Quick Reply: Titanium can't take the heat?



All times are GMT -5. The time now is 03:16 AM.