Stainless Works Chevy Corvette 2001-2004 Headers: 1-7/8" with Converters - Manual

C5 HEADER INSTALLATION INSTRUCTIONS
Thanks for purchasing Stainless Works headers for your C5 Corvette. We have gone to great
pains to make sure that our headers fit and perform flawlessly. Please follow these steps to
ensure that your installation goes as planned.
1. Remove factory manifolds and H-pipe assembly. Disconnect all air tubes and O2 sensors
before removing from car. We also recommend disconnecting the battery and ECM
before welding.
2. Install headers by inserting passenger side header in from the top, and driver side header
in from the bottom. On the passenger side, unbolt the starter from block and set forward,
do not remove the starter from vehicle. On the drivers side, loosen the motor mount bolts
as raising the engine partially may be required. Also remove the steering shaft to allow
clearance to install header from underneath car. Install the factory gaskets in between
header flange and block- if the car is a Z06, you will need to purchase the standard C5
round port LS1 exhaust manifold gasket kit since the headers we supply are full round
port. Tighten bolts holding flange onto head, and then tighten bolts underneath between
support tabs and rear mount. If your headers are equipped with the ¼” cylinder head
flange, you may need to shorten the factory manifold mounting bolts or use washers
underneath the heads so that the bolt does not bottom out in the cylinder head. A shorter
bolt with the same thread is available through your local GM dealer under GM part #
12556127. Headers with the 3/8 flange do not need to use washers or shorter bolts.
3. Install O2 sensors with never-seize on the threads- be sure not to touch or get never seize
on the O2 element.
4. Cut H-pipe at inlet to converters through the weld, so little or no weld is left on inlet of
converters. Depending on the year of the car it may be necessary to shorten the h-pipe
after the catalytic converters so that the adapter inlet lines up properly with the collector
outlet.
5. Remove the two short stubs of material that are left in the inside of converter inlet (the
factory h-pipe is double walled).
6. Clean and deburr inside diameter and outside diameter of converter inlet.
7. Insert Stainless Works adapters and install H-pipe on car to ensure correct alignment.
8. Tack adapters to converters in 3-places to minimize distortion
9. Remove H-pipe and finish weld.
10. If tubing becomes out of round from welding heat, re-round in bench vise or c-clamp
using wood blocks to evenly distribute pressure.
11. Install H-pipe using red high temp RTV on slip joint at front of H-pipe. Tighten supplied
band clamp.
12. Reinstall O2 sensors and air tube fittings. Check all fasteners for proper torque (see your
factory assembly manual for proper torque specs).
WWW.STAINLESSWORKS.NET 800-878-3635 FAX: 440-543-9183