| From | Message |
Polk
Dodge Dakota
JOIN HERE
4/19/2004
01:30:02
|
 Subject: Question For A School Project
IP: Logged
Message:
I have a project to do in one of my classes and I decided to do it on headers since I'm looking to get some. The whole project is to find out which material would be the best to use given certain mechanical, chemical, and thermal characteristics of three different materials. So my question is what is the hottest temperature (under normal operation, not overheating) the engine could possible get? Also, if anyone has any input, what are some things that the headers will experience and what characteristics do they need? (such as hot temperatures, possible debris hitting them, water spraying them when hot, need to be lightweight, inexpensive, etc.) Any help for an "A" in the class would be appreciated. By the way, this is a college engineering course so you don't need to be as elementary as I'm probably sounding.
Jason
|
CThomp
*GenIII*
4/19/2004
08:30:24
| RE: Question For A School Project
IP: Logged
Message:
You should contact JBA, Gibson, or Borla with those questions. They do make headers after all. Get in touch with customer service and explain you plight to them. I'm sure they'd be willing to help.
|
DSW
Dodge Dakota
JOIN HERE
4/19/2004
17:51:21
| RE: Question For A School Project
IP: Logged
Message:
It realy doesn't matter how hot the engine is running since the engine could be at 180 degrees while the headers are at 1000 degrees. Headers are pretty thin tubing with exhaust gasses and unburned/burning fuel "flames" shooting down the tubes, things can get glowing red hot if the engine is realy rapped up.
Paint an engine and it will look good for years, paint headers and it produces a big smoking foul odor cloud as the paint is burned into and off the headers after the headers are installed. Months later the painted engine will look great while the headers will look terrible since the paint has mostly burned off the headers.
Looks like you need to find out what temperatures headers are subjected to instead of the engine itself.
|
Polk
Dodge Dakota
JOIN HERE
4/20/2004
09:07:44
| RE: Question For A School Project
IP: Logged
Message:
Ok, that's the kind of stuff I needed to know. I e-mailed JBA yesterday and I'm waiting on a response now. Does anyone have any ideas on anything? This is a very open ended project. I can take it anywhere I want to.
Thanks for the responses so far.
Jason
|
bump
Dodge Dakota
JOIN HERE
4/20/2004
09:09:57
| RE: Question For A School Project
IP: Logged
Message:
More like 4000 degrees , fully warmed up
@ Wide Open Throttle & a little NOs to help..
|
CThomp
*GenIII*
4/20/2004
09:32:01
| RE: Question For A School Project
IP: Logged
Message:
I'd shoot an email to all of those companies. Hoping that one company will respond is a long shot. I'd also shoot Thorley and Hedman an email. They've been building headers for a long time.
|
MY H3RO
Dodge Dakota
JOIN HERE
4/20/2004
11:42:21
| RE: Question For A School Project
IP: Logged
Message:
I have had Cyclone AR (anti-reversionary) headers on my 77 Vette for over 20 years. They have an aluminized coating and except for an occasional retightening of the bolts, they still look like new. 4000 degrees? Steel melts at 2200.
|
Mr.Sleepy
Dodge Dakota
JOIN HERE
4/20/2004
13:00:47
| RE: Question For A School Project
IP: Logged
Message:
Just a thought, Gibson/JBA/Flowmaster probably could tell you but how about finding someone with headers. Any car would do I would imagine since you said your project was about headers, not dakotas with headers. Borrow a infared temp sensor, warm up the engine and take a couple of readings.
|
Bowtie-ZL1
Dodge Dakota
JOIN HERE
4/20/2004
22:10:47
| RE: Question For A School Project
IP: Logged
Message:
High carbon steel melts at 2500*F-- low carbon structural steel melts at 2700*F.
|
Tnjones
Dodge Dakota
JOIN HERE
4/21/2004
17:06:10
| RE: Question For A School Project
IP: Logged
Message:
Exhaust Gas Temperature is critical to designing tuned headers due to the changes in density and viscosity caused by temperature variations. The 2 stroke motors I used to put tuned pipes on had EGT's of around 450-480 degrees if I remember right. There must be an ideal temp for efficiency in 4 stroke motors since EGT is one way a modern engine's computer decides how to adjust the fuel air mix. Besides, any race tuner can tell you leaner is hotter, richer is cooler. A little web research should get you that exact 'best' temperature.
Keep expansion rates in mind when specifying your material. Those pipes are mechanically connected on both ends.
The mix of compounds and elements in exhaust gas is highly corrosive. Especially if allowed to oxidize (as evinced by the tip of your exhaust pipe rusting through way before the rest of the pipe). Another important factor in selecting material.
Resistance to stress fracturing is also important. Ever notice how your motor rocks on it's mounts when you rev it? A properly mounted exhaust system keeps this stress to a minimum, but it can't be totally eliminated. Bear in mind torsional stress under both low (starting the motor when it's 20 below or colder) and high temperatures.
|
stevieb92
Dodge Dakota
JOIN HERE
4/21/2004
17:21:00
| RE: Question For A School Project
IP: Logged
Message:
A thermodynamic analysis of the engine cycle should get you in the ball park for the EGT. If you haven't had thermo yet, I suggest you read up. The equations aren't that difficult as long as you understand the parameters. THe EGT is probably the largest factor in the search for the best material for headers. Just my $.02
|
Polk
Dodge Dakota
JOIN HERE
4/22/2004
15:26:36
| RE: Question For A School Project
IP: Logged
Message:
Ok, this is a lot of stuff that I wasn't even thinking about. I haven't had thermo completely yet. I started it this semester, but with the other classes I had and I work 25 hrs a week so it put too much on my plate. I do remember some of the stuff at the beginning though. I'm finally getting a couple of responses from the companies I e-mailed and I am going to call another at their request. So hopefully this will turn out being a great project and I'll be buying some headers before long. Thanks a lot yall.
Jason
|
oh my god
Dodge Dakota
JOIN HERE
4/22/2004
18:09:29
| RE: Question For A School Project
IP: Logged
Message:
4000 degrees !! LMFFAO!!!! how far up your bung did you reach to pull that one out?????
make your own out of 1/8" wall 303 or 304 stainless and they will outlast the car/truck
|
big_torque
Dodge Dakota
JOIN HERE
4/22/2004
18:44:13
| RE: Question For A School Project
IP: Logged
Message:
In your paper you could also talk about:
How they are made
The different types and how the effect performance
1 shorties
2 mid
3 longtube
The components that make up the header:
-flanges , tubing , welds
How they free up exhaust flow
The pros and cons of them.
Header coatings
History of headers ? lol.
Good luck , sounds like a fun project.
|
| | P 1 |
|
Post a reply to this message:
Username Registration: Optional
All visitors are allowed to post messages
|
