What's the easiest way to...
What's the easiest way to install headers into a Second-Gen Firebird? Certainly with the engine out, but that's not always possible. We discuss the 12 most common issues owners deal with during installation.
Many Second-Gen Firebird owners have installed tubular headers because they typically allow an engine to produce maximum power over a wide rpm range and are a popular "speed part" choice amongst performance enthusiasts. Though there are a large number of headers on the market today, some low-cost units are cheaply made and fit poorly, while it seems that higher quality (and more expensive) offerings fit best and provide the least amount of installation headaches.
When dealing with the Second-Gen Firebird chassis, there are many potential areas of concern that seem common to all models, so we touched on 12 that one would most likely encounter, offering simple suggestions to remedy each. While we must caution that there may be obstacles, which are unique to a vehicle and must be dealt with on a case-by-case basis, we hope to simplify the installation process, thereby minimizing headaches and maximizing your Firebird's performance.
Special thanks to Jim and Tom Hand for their assistance with the preparation of this article.
Tubular headers are designed...
Tubular headers are designed to maximize engine performance within a particular rpm range by using primary tubing of various diameters and specific length and diameter collectors. Many variations are presently on the market, but it seems that the highest-quality units offer the best fit.
1 - Solidly Mounted Worn...
1 - Solidly Mounted
Worn engine mounts are most apparent when sorting out Shaker positioning on a Second-Gen Trans Am, but they can also wreak havoc when installing headers into any Firebird model. Not only do worn mounts place the header flanges in closer proximity to the subframe crossmember, they also reduce ground clearance and abnormally tilt the engine. This can affect alignment with the remaining exhaust system. New rubber stock replacements are available from your nearest parts store, while urethane replacements for some applications are available through mail-order suppliers.
2 - Control Arm When installing...
2 - Control Arm
When installing headers, the lower control arm bosses can be major obstacles as the primary tubes snake around them. Clearance is often very tight, leaving little space for the control arms' bolts and nuts, and the fuel and brake lines that run along the subframe.
2 (cont.) - One suggestion...
2(cont.) - One suggestion prior to header installation is to remove the control arm fasteners and reinstall the bolts and nuts so that the nuts face the collector instead of the bolts. This way, the bolts can easily be extracted while the headers remain in the vehicle. It will definitely make front suspension work much easier in the future.
3 - Close Quarters Some owners...
3 - Close Quarters
Some owners searching for headers might ultimately choose the pair that tucks up nearest to their Firebird's floorpans. What many don't realize is that close-fitting headers can make contact with underbody flooring when the transmission is placed into Reverse and the body twists in the opposite direction. A solution for this scenario might include a large hammer and some rudimentary underbody work.
4 - Collector Clamps The...
4 - Collector Clamps
The use of a slip-type collector flange can provide as much as an inch of additional ground clearance.
4 - Collector Clamps (cont.)...
4 - Collector Clamps (cont.)
A traditional collector flange consists of a triangular-shaped piece of 1/4-or 3/8-inch thick metal that mates to a similar unit on the exhaust pipe. A gasket is used between them to prevent leaks. The slip-type flange eliminates the need for the flanges, maximizing clearance under a low-slung F-body.
5 - Automatic Trans Anatomy...
5 - Automatic Trans Anatomy
The vacuum modulator on an automatic transmission controls part-throttle up-shifts, and the original unit installed onto the Turbo 400 was much larger in diameter than some of those found on the smaller Turbo 350, so it may not be compatible with most headers. A common cure is to install a smaller Turbo 350-style modulator or an aftermarket adjustable unit and reroute its vacuum source accordingly.
5 (cont.) Steel lines that...
5 (cont.)
Steel lines that run along the side of the engine oil pan carry fluid to and from the automatic transmission and radiator or auxiliary cooler. They oftentimes interfere with the primary header tubes. Because the transmission fluid is under high pressure, splicing into the steel line and adding a small length of rubber hose is an unacceptable and dangerous solution. Custom-bent cooling lines are a practical choice.
6 - Manual Trans Malady Hobbyists...
6 - Manual Trans Malady
Hobbyists who own manual transmission-equipped Firebirds may not have vacuum modulators or transmission cooling lines to contend with, but one element that's equally as critical is the mechanical clutch linkage. The primary tubes of some headers may directly interfere with the upper or lower pushrods, and/or countershaft inhibiting proper clutch actuation. Fabrication and/or relocation may be required with some headers.
7 - Lock-Rod Limbo Whether...
7 - Lock-Rod Limbo
Whether it's equipped with an automatic or manual transmission, all Second-Gen Firebirds feature an upper gearshift control rod, which locks the steering column when the floor-mounted shifter is placed into Park (automatic), or Reverse (manual). Many headers do not provide sufficient clearance to retain this rod or its linkage. It can easily be removed and the column left in the "Lock" position, but drivers must be aware that at any time during operation, the ignition key can be manually rotated to the lock position, which will subsequently kill the engine and lock the steering column.
8 - Starter Solutions Most...
8 - Starter Solutions
Most headers have no real clearance issues with a stock-type starter that's already in place, but trying to remove or reinstall that starter can be difficult. Add an aftermarket oil pan, such as the Canton road-race unit shown here, and a stock-type starter may not even be an option. Fortunately, there are a wide variety of high-torque mini-starters available, such as this unit from GPE Competition Starters.
9 - Fat Flanges A common...
9 - Fat Flanges
A common complaint about headers is an exhaust leak where the flange meets the cylinder head surface. The leak is often the result of overzealous owners who over-tighten fasteners, distorting the thin-gauge flange commonly found on cheaper headers, which may not have even been flat when new! Higher-quality units typically include thick flanges that resist warping-this is an area that should be considered when shopping for headers.
10 - Great Gaskets A steel...
10 - Great Gaskets
A steel exhaust shim (top) is suitable when installing cast-iron exhaust manifolds, but high-quality offerings like the Fel-Pro piece on the bottom provides maximum sealing and is the best option when installing headers. Fel-Pro No. 1424 fits all D-port applications, while No. 1436 is for round-port applications.
11 - Installation Equipment...
11 - Installation Equipment
A common header shortcoming is maintaining fastener tightness. While locking header bolts are an excellent choice, using such products may not be an option when working within the tight confines of the Second-Gen Firebird engine compartment. Sometimes the header flanges are too closely located to adjacent components, requiring the use of short, six-point header bolts. A few unique and/or custom-made end wrenches can simplify the task.
12 - Filter Fitment The stock...
12 - Filter Fitment
The stock PF-24-type oil filter is sometimes too closely positioned to a header's primary tubing or collector. One remedy to gain collector clearance is simply to install a shorter filter such as those designed for certain Cadillac V-8 applications.
Bonus Tip: Ram Air Revelation...
Bonus Tip:
Ram Air Revelation
For those enthusiasts wanting header-type performance, but who might find installation somewhat intimidating, modern reproductions of the high-flow exhaust manifolds originally found on the Firebird's Ram Air, H.O., and Super-Duty engines are available from a few sources. The one shown here is from Ram Air Restorations. Available in D-port and round-port configurations, near-header performance levels can be attained, while maintaining stock appearance and fitment.