T.R | Title | User | Personal Name | Date | Lines |
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139.1 | | VMSNET::M_MACIOLEK | Four54 Camaro/Only way to fly | Tue Jul 19 1994 09:58 | 28 |
| Equal length headers, or headers which are tuned, work better than
"non-equal" headers. As each pulse goes down a tube it
works to help suck a just fired cylinders exhaust out. This is
called scavenging. On headers with different length primary tubes
they don't work as effectively, since they don't always help properly
scavange the cylinder. They do however FIT into a particular chassis
easier, and they do COST a bunch less. As far as over all benefit,
I don't know what a tuned set vs. non-tuned set would be. Even
a car with a non tuned set of headers is a heck of a lot better
that a stock exhaust.
re: Finish.
You can look good, or you can run good. The 4 finishes I'm familiar
with.
Stock paint, lasts about 2 minutes. Upon first fireup, the paint
burns up, and the headers will eventually be coated with rust.
Aluminum coated. Look nice forever.
Chrome. Look nice, but they're HOT. HOT HOT.
Thermal wrapped. Looks horrible, but it keeps your engine bay
cooler. This may be the ticket.
You also need to select the primary tube size carefully so you don't
kill your low end torque.
MadMike
|
139.2 | A fifth choice............ | SANTEE::AUGENSTEIN | | Tue Jul 19 1994 10:58 | 49 |
| Nowadays, the hot tip (so to speak) is to get ceramic coatings on the headers.
These are available from High Performance Coatings, Jet Hot and others, and many
header manufacturers are now supplying their products already coated this way.
The advantage is that the coating is very durable, but also that it acts as an
insulator to keep underhood temperatures down, and exhaust temperatures *up*,
which is what you want to keep exhaust velocity up, which enhances scavenging.
Theoretically, equal length headers work the way Mike said they did, but with
the additional data point that these headers will tend to enhance the torque
curve more at some specific rpm (due to their "tuned" length) than at other
points. Non-equal length headers will tend to enhance the torque curve across a
broader operating range, but less effectively than the equal length headers do
at or near their "tuning point". Some headers (and, for that matter, intakes)
are designed to have multiple tuning points to broaden the torque curve.
As a practical matter, equal length "shorty" headers tend to make more power
than non-equal length shorty headers on 5.0 Mustangs. However, the equal length
headers are a bear to install, and you may have interference problems with the
shock towers after installation, due to the vagaries in the mass production
method of building cars. Eric Goehl can tell you a lot about this stuff, since
he has a pair of equal length headers on his 5.0, and ran point on the
installation of a pair of non-equal length headers on my son's 5.0.
If you have a stock or near stock engine, and plan to keep it that way, go with
1 1/2" tubes. If you have made (or plan to make) significant mods, go with the
1 5/8" tubes. Eric has 1 5/8" tubes on his GT40+ car, and my son also has 1 5/8"
tubes on his Vortech equipped machine.
To recap:
1. Go with ceramic coatings. Use thermal wrapping if you don't mind the looks
and want the lowest possible underhood temperatures and the hottest exhaust
temperature. As a minor warning, using thermal wrap on the street (meaning 10s
of thousands of miles of use) may shorten header life a bit due to the ungodly
temperatures the tubes get subjected to.
2. Be realistic about how much hassle you're willing to put up with in
installation (you may need to jack the engine) and everyday use. There's nothing
quite like the sound of a header pipe in contact with a shock tower when you're
at full throttle and going over a minor bump. I pretty much guarantee you that
the clearance (if any) on your car will tear tissue paper to shreds :-).
3. When in doubt about pipe size, go with the smaller choice. As an example,
1 5/8" tubes on a stock engine will probably slow you down (either equal or
non-equal length) due to the loss of low end and some mid range torque.
4. Ford Motorsports and MAC are good names.
Bruce
|
139.3 | 5.0L headers | RICKS::CALLANDER | | Tue Jul 19 1994 20:43 | 23 |
| jc,
I think Bruce and Mike covered most of your questions. I have
MAC 1 5/8" equal length shorties in my "mildly" modified '91 5.0. I used
thermal wrapping to help keep the heat down. It works great but doesn't look
great. You will have to loosen up the motor mount on the passanger side and
jack the engine up about as far as it will go to get the header on that side.
They don't hit anything but they were a real pain going in.....
If I was doing it again I look into the ceramic coatings and probally
go for non-equal length for ease of installation and maintainance. I don't
think the power difference is that great. I have not seen a "street legal"
full length header setup for the 5.0 since the stock H-pipe and CATs would
have to go.
Finally I'm not sure what you have done to your car but headers would not
be near the top of my list of things to do first. I'd look at underdrive
pullies, and intake mods(mass air sensor,throttle body, intake manifold..)
before doing the headers. I saw little to no performance improvement on
my car when I added the headers. Maybe the 1 1/2" tubes would have been
better, but I'm still planning more changes so I went with the larger tubes.
/Mike
|
139.4 | Oh Yippee.... | STRATA::LAMOTHE | Jack of All Trades | Wed Jul 20 1994 19:16 | 11 |
|
headers are a Pain in the beehind....Everytime I want to change my
spark plugs i have to remove the headers...not to mention that one
must also be removed when a starter needs replacing.
Oh yeah...installing headers on a stang, you will need a relocating
bracket for the Power steering pump...
/Bob
|
139.5 | Not all headers are alike | SANTEE::AUGENSTEIN | | Fri Jul 22 1994 10:29 | 28 |
| On late model 5.0s, many headers (such as the non-equal length coated Ford
Motorsports model) will just flat bolt on, and not cause interference problems
with *anything*.
I am not a lover of these largely infernal inventions, but I must say there are
currently some good ones out there........
To pick up on the point Mike C. was making, headers will not be a waste of
money, but in point of fact, the 5.0 Mustang combo (like the TPI Chevy) is an
*extremely* well designed powerplant - from the viewpoint that everything is
designed to work well with everything else. The fact that the torque curve falls
off in the 4000s is not due to an exhaust restriction. It's due to the overall
design of the powerplant, including the heads, and *especially* the tuned
intake, which gives you extra torque at the low end and in the mid range, but
cuts off the top end.
The exhaust on these cars is very well designed to work with stock or lightly
modified engines - unless your cats are beginning to plug up. In that case, you
need to replace them. Ford had (has) a recall out on certain model-year 5.0s, so
you might want to check with a dealer.
Jeff, you might want to make a few quarter-mile passes with the car. This will
tell you whether or not you have a problem.
Also, when you get the time, by all means browse through note 58, *all* the way
through :-(.
Bruce
|
139.6 | | CXCAD::C_WILLIAMS | Hammer | Thu Jul 28 1994 14:54 | 54 |
|
Hey Coop,
Here's a story or two and my personal advise on headers. I can't
help you much as I don't know those old Mustangs (knowing yours
is a, what, a '67? An old one anyways.). But I have dealt a bit
with these tubular thingys.
Personally, I prefer to look into stock options, as I have learned
with my Pontiac dealings. Pontiac used to make 'stock headers'
which are pretty good and they fit without much of a hassle. Any
other header I've tried, or have helped friends try on their
Poncho's, have been nothing but trouble. For what extra ponies you
get out of them, some times it's just not worth it. Some times you
have to unbolt them to change plugs, sometimes to change the oil
filter. In the Pontiac case, the stock headers are basically cast
uglies but they work well. Oh ya, they're also difficult to find
and expensive (there's one place that casts repro's when they feel
like it (once a year or so)).
As was said in the past, ceramic coated headers are the best.
Prices are almost reasonable now as they're becoming more popular.
Personally, I'd stay away from the wrap as it tends to trash the
headers (they rot/rust/warp/crack easier). That's cool to do if
you're into some SERIOUS racing. As was semi-mentioned earlier,
the hotter the exhaust, the better, but really it's the larger
the temperature differential from your intake to your exhaust, the
better.
The dufus that I bought my 400 from had some headers on. They hung
VERY low below the car's subframe. Two tubes on each header were
smashed completely flat (pinched completely off) from his bouncing
them on the road or speed bumps or what-ever. I was able to find
some untuned headers that fit up under the subframe. They fit okay
but I ended up moving my oil filter. A buddy of mine just went
through hell trying to find some headers for his '72 GTO that would
fit up under the subframe. His old ones were slightly smashed from
hanging low and he had to take one off every time he had to change
his oil (he did it every 1000 miles, too!). He eventually decided
to go with the old stock headers (not the stock exhaust) but he
couldn't find any available. The untuned "supposed to fit up under
the subframe" headers he bought don't. He has already dented one
on the guide rails at a local emissions place. He's gone to a
smaller oil filter and can now change it without removing the
header so he's a little happier.
As for newer cars, I believe the engines are pretty much designed
with the exhaust system in mind and thus headers are a rip-off.
Just some food for thought.
Carl.
|
139.7 | | KDX200::COOPER | Revolution calling! | Mon Aug 01 1994 15:50 | 12 |
| Wow - Great advice here...
RE: Carl
Read again man - the '67 is long gone, this is an '87, 5.0L, 5spd.
I got tired of spending more time UNDER the car than in it. Besides,
the 5.0 will eat that '67s lunch.
I'm off to read the mustang note. :-)
BTW - I just replaced the clutch with a CenterForce - Yowza!
|
139.8 | kinda header related question | CXCAD::FRASER | | Tue Aug 02 1994 08:12 | 11 |
| Hi,
This is not a header question but damn close. I made a set of torque tubes
to better tune my exhaust. I remember reading how to tune them a while ago.
What I remember is you paint a stripe down the tube and make a pass down the
drag strip. Take the tubes off and cut them either 1/2 inch before or after
the stripe discoloration stops. Thats the part I don't remember. Before or
after ??? Anyone out there know ????
Thanks,,,
Brian...
|
139.9 | Won't the paint chip, chrome discolors, the marker runs. | VMSNET::M_MACIOLEK | Four54 Camaro/Only way to fly | Tue Aug 02 1994 10:04 | 5 |
| I believe you cut right where the discoloration occurs. Usually
you use a grease marker, and where the marker starts running is where
the optimum place to cut is.
MadMike
|
139.10 | Still confused | CXCAD::FRASER | | Tue Aug 02 1994 13:00 | 6 |
| RE:-1
Cut right where the discoloration occurs ???
The discoloration starts at the header flange and runs down the pipe for
18-20 inches....
Brian...
|
139.11 | Clarification on task at hand | VMSNET::M_MACIOLEK | Four54 Camaro/Only way to fly | Tue Aug 02 1994 15:15 | 6 |
| Maybe I should clarify what I think your asking for:
You're trying to determine the optimum length of the pipe after it
leaves the collector? Is your description of a torque tube, a
tailpipe, about 2 feet long which bolts to the collector?
|
139.12 | | VMSNET::M_MACIOLEK | Four54 Camaro/Only way to fly | Tue Aug 02 1994 15:24 | 16 |
| Assuming that's so, and you've painted the pipe all the way down and
the paint is chipping off all the way down the pipe, it sounds like the
pipes may be too short.
(not to scale)
|-------------------------------------------------------
|//////////////////////////////////////// 4" tailpipe
|////////////////////////////////////////
-------------------------------------------------------
^
^Collector flange Cut here
//// = discolored pipe, chipped or scortched paint, or runny marker wax.
You mentioned a 1/2 inch either way, I've heard to cut it right at
the point where the test media stops melting.
|
139.13 | Yup thats it... | CXCAD::FRASER | | Tue Aug 02 1994 15:34 | 10 |
| Yes we are talking about the same thing. I had heard 1/2 inch one way or the
other but I don't suppose it will make that much difference. Thinking about it
now, it is probably kind of silly to be worried about the enth degree of
perfection in the exhaust system when the car will most likly only run in the
high 15's anyway... I'll just cut them at the discolor line and leave it at
that. The car will only be run for one test and tune night and then for the
super chevy show on the 20th and 21st and then become a garage queen again
anyway...
Brian...
|
139.14 | ...Than add material back on. Cut it on the long side. | VMSNET::M_MACIOLEK | Four54 Camaro/Only way to fly | Tue Aug 02 1994 15:38 | 1 |
| Remember, it's easier to keep cutting...
|
139.15 | | TROOA::SCHABEL | Klatter-motor-pilot | Wed Aug 17 1994 10:26 | 17 |
| The headers in my '78 Stang actually made my life easier. The stock
single exhaust sucked(no punn intended). I ended up installing a set
of full competition Hooker headers. I had them nickle plated before
installation and years later they still look great. They greatly
increased the way the car breaths and performs(great!).
I did have to get an exhaust shop to flair one end and reduce the
other end of a couple of pieces of pipe to use as reducers to the
dual exhaust system in place. Everything fits so nicely that I can now
change all 8 spark plugs in about 20 minutes as opposed to the nuckle
breaking job with the stock manifolds.
The drivers side came as one piece while the passenger side came as
three separate pieces that slide together. These pipes even matched up
when the motor/heads were changed to 351W pieces.
As cutting torch(flame wrench) and impact gun came in real handy.
gary
|
139.16 | Headers for sbc - 67 camaro | IAGO::PROVENCAL | | Wed Apr 24 1996 09:58 | 17 |
| Hi,
I have a 67 camaro - 327 sbc. We have a pair of headers we put on a couple of
years ago.. nothing fancy... but, each year we have to take them off, sand them
down and re-paint them with a high temperature paint.. so taht they look okay.
My husband wants to buy a new set this year. Not sure which to go with?
I've read a little about the ceramic coated, and also saw mention of
aluma coat?.. Any input on these. Price ranges.. how long they stay
looking good, performance, etc?
I think the ceramic coated ones he was looking at were around $350.. was hoping
to not spend that much.. but we'll see what happens.
Thanks,
Cathi
|
139.17 | Works best with unused metal | NASEAM::READIO | A Smith & Wesson beats four aces, Tow trucks beat Chapman Locks | Wed Apr 24 1996 13:08 | 11 |
|
I had my headers done with that ceramic jet engine coating. They came out
pretty good
There are a couple of places that do it, HPC and Jet Hot Coatings come to
mind. HPC has a shop in Manchester CT right next to American Wheel. I
took mine down there and they mailed 'em back.
One of the problems you'll have is that your headers are "used" so they'll
have to be cleaned before they can be coated. The coating is on the inside
and the outside so they MUST be cleaned or be new when you get it done.
|
139.18 | go for new... | BSS::BOREN | | Wed Apr 24 1996 19:17 | 18 |
|
jet hot can take the old ones and refurb them...but your working with
potential corrosion after the couple of years, and getting them done
afterwards does not give the lifetime expectations that a new set
(coated would).
I went through the same problem, ended up just going for a new coated
set to replace the 'rusty ones' on my '74 V8 Vega, on my '57 BelAir
I found new chrome headers for about the same price as coated ones from
Hooker...I went with the chrome, and I actually think the chrome
headers are holding up much better and probably will outlast the coated
headers. IMHO.
recommendation: get new headers (chrome or coated) and save the old
ones for an emergency or flea market material.
rich
|
139.19 | trade-offs | NASEAM::READIO | A Smith & Wesson beats four aces, Tow trucks beat Chapman Locks | Thu Apr 25 1996 16:21 | 7 |
|
Chrome headers are only coated on the outside and will suddenly develop
rust-through passages if the headers aren't heated enough to burn off all
moisture. Jet Hot and HPC ceramic coatings are electro-statically applied
to the outside and inside and provide better long term use. Appearance may
not hold up as well (bright, shiny chrome vs. dull ceramic) but the pipes
sure will.
|
139.20 | If I ain't going any faster I just let mine burn | VMSNET::M_MACIOLEK | Four54 Camaro/Only way to fly | Mon Apr 29 1996 13:52 | 11 |
| I had BlackJack AK5000's I think, AK something, on my old Camaro.
They're aluminum coated, and economical. If all you want is a pair
of headers that look the same several years after you put them on,
this'll do it.
Chrome creates HEAT. Coating is nice because you can get fancy
colored headers on a pair of tuned headers that meet your
requirements. But now your spending money.
Regards,
MadMike
|
139.21 | Ceramic Coated won | IAGO::PROVENCAL | | Wed May 01 1996 12:29 | 4 |
| Thanks for all your input. We went with a pair of the Ceramic Coated Headers.
I'll let you know how we make out.
Thanks again!
|