Corsa Install

The stock
Corvette
exhaust system works well and sounds pretty good.
Actually, it’s sounds
polite and politically correct. From my
first test drive, I thought that
the exhaust note was a little
weak, even under wide open throttle. Heck,
my Mustang’s stock
exhaust (gasp!) had more grunt. Not being a civilized
type of
person, I went looking for replacement options.

Corsa makes the
exhaust
system for the Corvette Indy Pace Car. I talked to
people about DynoMax,
Flow Master, B&B and all the others. My
biggest gripe about aftermarket
systems was the exhaust drone
during cruise. Resonance is a gremlin that
many manufacturers
try to eliminate but to my knowledge, many aren’t successful.
During my research, one thing I kept hearing was how wonderful the Corsa
system was at cruise speed. People also told me that it was an
animal
at full throttle and had a wicked snap crackle pop when
you let off. That
was enough for me! I placed an order with C5
Concepts and waited my gleaming
stainless steel wonder to
arrive.

One other thing…
Corsa makes two systems, the Indy
and the Touring. From what I understand,
the Touring system is
quieter all around. So, what’s the point?

It helps an immeasurable
amount if you have the car off the ground for an exhaust install. This
is always an adventure with the low slung C5. The small space
provided
by jack stands is better but still a major hassle. I
made arrangements
with a local shop to come in on a Saturday
and use one of their lifts.
Well, that was the idea. None of
their lifts could accommodate the C5.
I was about to give up
when I noticed their chassis straightening rack.
It was about
three feet off the ground and the Corvette rolled right up
without scraping. With the car safely off the ground, it was time to make
the swap. It’s also worth mentioning that you’ll want a
friend to help.

The Corsa instructions
are
good but not totally complete. They do have a good complete list of
all the tools required. The first thing to do is to remove the four bolts
that connect the rear sway bar to the chassis. You can then
let the sway
bar just swing down out of the way. Next, unbolt
rear of the exhaust system
from the collectors aft of the
catalytic converters. Now remove the bolts
that hold the
mufflers to the frame (via a rubber mount). If you have
an
automatic transmission, you’ll need to remove the heat shields first.
Now, wiggle and squirm and contort the stock pipes over the
axle and out
from under the car. It may not seem like it, but
it is possible.

Now it’s time to install
the Corsa
system. First put the over-axle-pipes in place. Do the mufflers
one at a time or you’ll stop dropping parts. Put the rubber mounts on
the Corsa mufflers and hoist them into place. Put in the bolts
loosely
and slip the exhaust pipes into place on the mufflers.
Now move the flanges
together up front and slip the gasket
into place. Goop up the bolts with
anti-seize and put them all
in place. Make them finger tight for now.
Make sure you don’t
get any anti-seize on the stainless steel because
it’ll stain
the finish. Now you’re whole system should kind of be hanging
by a thread. It’s time to tighten everything up and make it look good.
This proved to be the hard part. The muffler brackets should
be tightened
to 12 foot pounds. Make the flanges reasonably
tight. You need to adjust
everything so the exhaust pipes are
level and so they’re not touching
any plastic. Start by
bolting the flanges up tight. Mine leaked so you
might have to
use the old gaskets or play with them for a while. Now put
the
U bolts over the pipes at the mufflers and get them snug. Adjust the
mufflers until they’re level and the pipes are the same distance away
from the plastic of the rear skirt. Make sure the pipes are
all the way
into the mufflers before tightening them up! Keep
tightening and adjusting
until everything is lined up at snug.
It’ll take a little while to get
it right but be patient. Be
careful not to over tighten the U bolts and
shear one of them
off. If you take the time, the results will be worth
it. When
everything is set, swing the sway bar back into place and install
the nuts. Torque the upper nuts to 49 foot pounds and the lowers to 70
foot pounds.

After everything is
done, fire
the engine up and check for leaks. Mine leaked at the flanges
and where the pipes enter the mufflers. Putting double gaskets on help
at the flanges and the mufflers finally seated on their own.
Many people
weld the pipes at the mufflers for a solid fit.

One side note. We
ran into a little problem due to
inattention to what we were doing. My
installation partner set
the torque wrench to 137 foot pounds instead
of 37 foot pounds
when I was tightening up the muffler brackets. [ed.
– the
muffler brackets should torqued to 12 foot pounds]. Needless to
say, I busted one of the studs off. This was a bad situation. The studs
mount to a plate inside the frame. The only access I could see
was by
taking off the entire rear clip. Being lazy (and
inventive) I came up
with a strange solution. I moved the
broken stud out of the way and used
a drywall spider anchor to
hold the bracket in place. It’s not a cheesy
as it sounds.
The mount is very solid and hasn’t loosened with time. The
moral of the story? Be careful and pay attention to what you are doing.

Was it worth it? Yes!
I like the way the
Corsa Indy system sounds. It’s sounds like a big block
motorboat at idle and a screaming demon at wide open throttle. Every
police
office within a two mile radius will hear it when you
open her up so be
careful. Instead of a mellow burble when you
let off the throttle, the
Corsa snap, crackle and pop like a
thunderstorm. The sound is very distinctive
and very cool.
Best of all, there is no annoying drone when cruising down
the
road. As far as horsepower gains? There will probably be a little
bit but the stock exhaust was pretty up to the task. Who knows, maybe
the Corsa combined with everything else will be the last little bit I
need to get into the high 12’s!