DOUG S HEADERS D3321-B Full Length Header Instruction Manual
- May 21, 2024
- DOUG S HEADERS
Table of Contents
D3321-B Full Length Header
Product Information – Long Tube Headers for 1982-1992 Camaro, 265-400
Small Block
The Long Tube Headers are designed for use in 1982-1992 Camaro with 265-400 Small Block engines. The product comes with a left and right side header, header gaskets, reducers, collector gaskets, header bolts, lock-washers, hex nuts, and spacers.
Note: To retain oxygen sensor, purchase Doug’s Reducer Part No. H7233.
Product Usage Instructions
DISASSEMBLY:
- Remove oil dipstick tube, alternator and its brace (on early cars, A/C pump and brace on later models). Remove the starter, clutch linkage, and fan shroud bolts.
- Unbolt stock head pipes from the exhaust manifolds and push aside.
- Note the spark plug wire locations and remove them from the spark plugs.
- Remove the spark plug wire looms and any brackets attached to the exhaust manifolds. Remove the spark plugs.
- Remove the exhaust manifold bolts and remove the exhaust manifolds.
CAUTION: Be sure to place a board between the oil pan and the jack.
INSTALLATION:
- Starting from below, work header up through chassis into position but do not install any bolts.
- Lower the motor and check for header clearance. Replace motor mount bolt.
- Using the supplied header bolts and lock-washers, apply a small amount of anti-seize to the bolts and start the most restrictive bolts first.
- Install the spark plugs and attach the appropriate wire to the spark plug and reattach the spark plug wire looms. It may be necessary to reroute wires to clear the headers.
- Starting from below, work header (without R-4 headpipe) up through chassis into position but do not install any bolts yet.
- Lower the motor and check for header clearance.
- Apply a small amount of anti-seize to 2 stock bolts. Install them in the front 2 bolt holes with the furnished spacers to hold brackets in the stock location.
- In the remaining bolt holes, use the supplied header bolts and lock-washers. Apply a small amount of anti-seize to the bolts and start the most restrictive bolts first but do not tighten.
- Replace motor mount bolt and fan shroud bolts.
- Reinstall the starter and install the R-4 headpipe in slip tube on the main body of header.
- Tighten header bolts evenly starting in the center.
- Reinstall the dipstick tube, clutch linkage, and the alternator.
- Install the spark plugs and attach the appropriate wire to the spark plug and reattach the spark plug wire looms. It may be necessary to reroute wires to clear the headers.
- Connect the negative battery cable.
PLEASE READ BEFORE PROCEEDING
PerTronix® thanks you for choosing a Doug’s Headers Product. To realize the
potential of Doug’s Headers engineering and excellent fit, Please Read and
Understand these instructions completely prior to starting the installation.
Check that you received all the parts listed on the parts list, if you have any concerns, please contact PerTronix before continuing. Headers will have the part number stamped in the flange. Many factors affect he installation of exhaust headers, including worn or aftermarket motor mounts, previous accident damage, aftermarket cylinder heads that may have relocated port or spark plug locations, suspension and steering changes, sagging of original unibody structures due to age.
Coating Notes: Coatings can be marred during installation if you are not careful. If you are breaking in a new motor, the extreme heat can alter the appearance of the coating and this is not a warranty issue. We recommend breaking in new motors with stock manifolds or an old set of headers. We use sealing beads on all our headers. The raised bead creates a better seal virtually eliminating leaks if installed properly. It is important to install all header bolts lightly snug and then tighten to factory torque specs starting in the center and working outward.
Before starting, allow the vehicle to cool, disconnect the battery, and spray a penetrating oil on all hardware and fittings that will need to be removed. Once you remove your manifold, clean the sealing surface on the head of any old gasket debris or carbon build up.
Work Smart – Work Safe! Most Header and Exhaust Installation are best performed on a lift. If a lift is not available, raise the vehicle and support on quality Jack Stands on level ground. Do not rely on a jack!
DISASSEMBLY
- Remove oil dipstick tube, alternator and its brace (on early cars, A/C pump and brace on later models). Remove the starter. clutch linkage and fan shroud bolts.
- Unbolt stock head pipes from the exhaust manifolds and push aside.
- Note the spark plug wire locations and remove them from the spark plugs.
- Remove the spark plug wire looms and any brackets attached to the exhaust manifolds. Remove the spark plugs.
- Remove the exhaust manifold bolts and remove the exhaust manifolds.
ASSEMBLY
-
Remove left side motor mount bolt and jack motor up approximately 1-1/2” – 3”.
CAUTION: Be sure to place a board between the oil pan and the jack. -
Starting from below, work header up through chassis into position but do not install any bolts.
-
Lower the motor and check for header clearance. Replace motor mount bolt.
-
Using the supplied header bolts and lock-washers, apply a small amount of anti-seize to the bolts and start the most restrictive bolts first.
-
Install the spark plugs and attach the appropriate wire to the spark plug and reattach the spark plug wire looms. It may be necessary to reroute wires to clear the headers.
-
Remove right side motor mount bolt and jack motor up approximately 1-1/2” – 3”.
CAUTION: Be sure to place a board between the oil pan and the jack. -
Starting from below, work header (without R-4 head pipe) up through chassis into position but do not install any bolts yet.
-
Lower the motor and check for header clearance.
-
Apply a small amount of anti-seize to 2 stock bolts. Install them in the front 2 bolt holes with the furnished spacers to hold brackets in the stock location.
-
In the remaining bolt holes, use the supplied header bolts and lock-washers. Apply a small amount of anti-seize to the bolts and start the most restrictive bolts first but do not tighten.
-
Replace motor mount bolt and fan shroud bolts.
-
Reinstall the starter and install the R-4 headpipe in slip tube on main body of header.
-
Tighten header bolts evenly starting in the center.
-
Reinstall the dipstick tube, clutch linkage and the alternator.
-
Install the spark plugs and attach the appropriate wire to the spark plug and reattach the spark plug wire looms. It may be necessary to reroute wires to clear the headers.
-
Connect the negative battery cable.
Note 1: To retain oxygen sensor, purchase Doug’s Reducer Part No. H7233.
IMPORTANT CHECK LIST
- Be sure that all brake lines, transmission lines, and fuel lines are clear of headers and/or connector pipes.
- All spark plug wires, battery cables, or other electrical components should be clear of headers and/or connector pipes.
- If dipstick tube was removed, make sure it is installed properly and that the dipstick has been replaced.
- Double-check the tightness of all bolts including brackets and accessories.
START THE ENGINE
Start the engine and allow it to warm up to operating temperature. Check for
any unusual noises or exhaust leaks. If everything is OK, stop the engine and
tighten all bolts while the engine is still warm.
NOTE: Check the bolts periodically to make sure they have not loosened. Re-tighten after the first 500 miles and then again at 1000 miles
PARTS LIST:
- 1 Left side header
- 1 Right side header
- 2 Header gaskets
- 2 Collector gaskets
- 2 Reducers
- 12 3/8”-16 x 1” header bolts
- 18 3/8” lock-washers
- 6 Hex Nut, 3/8”-16
- 6 Screw, cap, hex head, 3/8”-16 x 1-1/4”
- 2 1-1/4” Spacer
DOUG’S HEADERS LIMITED WARRANTY
All Doug’s Headers and Exhaust products are guaranteed, to the original
purchaser, to be free of defects in material and workmanship for one year from
date of purchase. This warranty covers the replacement or repair of the
product and does not cover the cost of removal and installation, customer
applied coatings, or Any discoloration or corrosion of finished surfaces.
Damage or product failure resulting from collision, improper installation, off road use, road hazards, the use of exhaust insulating wrap, or rust occurring after installation is not covered by the warranty. This warranty extends only to the original purchaser.
Should a part be deemed defective, it should be returned to the original selling retailer and must be accompanied by the sales receipt. If there is no retailer in your area, contact PerTronix direct for a return authorization and return the part prepaid to the factory for inspection. PerTronix reserves the right to replace or repair the alleged defective part and return the part freight collect.