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More
information than you'll ever need to know...
A
"header" is an aftermarket replacement for the original
exhaust manifold. Why do people use headers? Usually it is
due to the original manifold having been designed with
performance as a low priority. On many engines a header can
improve engine breathing considerably. With the Datsun
roadsters this is not the case as Nissan went to GREAT
lengths to make the original manifold a quality
item.
Then
why use a header on roadster? Price. If they were near each
other in price there wouldn't be a decision, but they
aren't. The manifolds are currently about 5 times the cost
of a header when WE CAN FIND THEM!
Although
the manifolds can be a bear to actually get out of the
engine compartment, once you get them near the engine they
fit like the cast and stamped part they are, great. Headers,
being a hand welded up product, do not have the luxury of
being as exact as a manifold. They do fit, but it's not out
of the question to have to put a little dent here or grind
this off there. Many times you don't have to, but no header
built out of the required-for-performance size tubing fits
all cars alike. Look at how the factory dented up the
original manifolds and you'll see how tight clearances are.
On
the other hand, once you get a header away from the head, it
comes right out. Getting an original manifold out of the
engine compartment sometimes requires raising the engine off
of the left mount.
Access
to the mounting studs can also be more difficult. You
thought that was impossible right? Thankfully someone
invented flex sockets, 1/4 inch drive socket sets, offset
wrenches etc! Actually it's the danged intake manifolds that
create the problem.
As
headers go (and we've seen a lot of different roadster ones
over the years) these are designed extremely well. Compared
to headers of the past, these are superb. A noted roadster
enthusiast worked with the original manufacturer of these
headers over the years to make them as good as possible.
Thanks Stan.
We
offer these two ways, bare or coated.
With
the bare ones you can use any hi-temp color paint you want.
Many people just use "stove black" but there is no reason
you have to be THAT boring if you don't want to! The most
popular colors seem to be silver (so it looks like the
original manifold), white, red or orange.
Or
get one with a high temp coating (not paint) that keeps the
heat in to keep the underhood temps down. The header
manufacturer has these plated by a professional plating
company that installs high tech high temp coatings.
Manufacturing and plating the headers in bulk has made the
price much more affordable.
To
install the header you will also need to have the original
flange removed from your front exhaust pipe and the adaptor
for the header intalled (usually welded) on to the
pipe.
If
you have a 1500 or 1600 starter on your 2000 you may find
that the header either won't clear the starter, or actually
touches the starter when installed. (Starters don't like
heat) The 2000 starters are about 7" long from the tip of
the most forward part of the housing (when mounted) to the
mounting surface that touches the engine plate. If yours is
much longer you will need to replace the starter with the
correct one. Typically the problem occurs with starters that
are 7 3/4" and longer but it varies by the header design. We
usually keep lots of these in stock. All of our starters
will fit with the headers. Speaking of starters, you may
find that the header will prevent you from removing your
starter without first removing the header.
We
want you to be happy and aware of what's what. We've been
taking this extra step for 30 years and it's worked. Nobody
likes to find out later what they should have been told up
front. These headers have been altered and tweaked a couple
of times to ensure as trouble free an installation as
possible.
Making
It All Live Longer...Manifolds
had a brace that ran from the front of the manifold to the
engine mount bracket. This brace serves two purposes. One is
to lessen stress on the manifold that is generated by the
engine jumping around with the exhaust system firmly
mounted. With the brace in place, the forces that are trying
to bend the manifold are reduced greatly because the
leverage is reduced. The brace also helps the manifold
gasket to live longer as the constant motion of the engine
in relationship to the exhaust system tends to eventually
crush the manifold gasket. Unless the manifold or header is
snugged down the gasket will eventually fail. The 2000
usually lets you know this by the presence of coolant
staining on the side of the engine block below and behind
the carbs.
Keeping
your engine properly tuned up will also increase gasket and
exhaust life. An engine that jumps around at idle is very
stressful on the exhaust system in general, the manifold,
the gasket, and even the engine mounts.
The
headers have no provision for such a brace but the above
described stresses can also be lessened by installing a
section of "flex" tubing just to the rear of your front
pipe's mounting flange. This is not the lightweight low
quality flex tubing popular in the 60's for "modificiations"
it is a webbed tubing that is used as original equipment
many cars. Almost any exhaust shop can fabricate this for
you.
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