C4 BOSE WOES: Repairing & Replacing 84-96 Bose Speakers & Amps

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If you own a C-4 equipped with Bose sound system, you will eventually need Bose amplifier repair or replacement. Every Bose sound system equipped C-4 uses one amplifier per speaker. This is the weak link. Amplifier capacitors are filled with electrolytic fluid which ultimately leaks out onto the circuit board causing failure. If the leak is slow, the amplifier’s circuit board can be damaged beyond repair. Electrolytic fluid is acidic and will corrode anything it touches.

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84-96 Door Outside Seal Strip Replacement

C4 Outside Seal Strip Replacement Lead Shot (1) (Medium)

Automotive door sealing technology has improved dramatically from the early days when rain water came in from all angles. By 1969 GM changed the outer seal strip that wipes the glass clear on those damp mornings to do a good job of keeping water out of the door. In turn it kept water off of the door internals and off the backside of the fiber door panels. By 1984 the door outside seal strip was an integral part of door glass sealing. The downside was they were the most exposed seal strips to date subjecting them to the effects of UV deterioration much quicker than previous year Corvettes. You can help keep them around longer with an application of rubber protectant to replace the rubber solvent compounds removed after each wash job. Products like Adams V.R.T. Vinyl Rubber and Tire Dressing from Corvette Central P/N 106824 will keep your outside seal strips looking good for many years. This dressing brings back that new look without that greasy oily slick look, you can also touch it without fear of it coming off on your hands or clothes.


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How do I install the new polyurethane rear differential bushings on my 84-96, as the bushing seems too large to fit?

C4 batwing bushing sleeveThe polyurethane bushings for the rear differential carrier or “batwing on a C4 measure 2 1/8” diameter on the portion that fits into the carrier hole.  When You press the original rubber bushings out, there is an outer “sleeve” from the bushing that remains.  This has to be removed as well.  One simple way to remove these sleeves is to cut them into a few sections with a hacksaw blade, then use a hammer and punch to drive them out.  Once that is done, the new polyurethane rear differential bushings should press in without a problem.

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Which Rocker Arm Is Right For Me?

Assembling the perfect valve train combination is challenging for even the most seasoned engine builders because there are so many variables involved. One area of the valve train that many people have difficulty with is selecting the perfect rocker arms. With a wide variety of options available, it can be hard to know which rocker is the best choice for your application. “Which rocker is right for me?” is a question that the technicians at COMP Cams® are asked every day.

HighEnergyThe three most important factors in deciding which rocker arm is right for your application are valve spring diameter (pressure), RPM range and valve lift. As these factors increase, you will need a stronger rocker arm because the stability and durability of your valve train depend on perfectly matched components. COMP Cams® Engine Builder Technicians pay close attention to valve lift when deciding which rockers an application requires.

For stock replacement rockers in applications where valve lift has not been increased, COMP Cams® carries High Energy™ Steel Rocker Arms. Although they feature a long slot for higher than stock lift camshafts, these rockers are engineered to handle the demands of only very mildly upgraded valve trains. They are best suited for eliminating the noise and slop associated with worn stock rockers.

HighEnergyDieCastWhen more aggressive upgrades are made to the valve train, COMP® technicians recommend Magnum Rocker Arms. As the ultimate in street performance, these rockers are designed to last longer and help the serious performance enthusiast make even more power in any application with less than 350 pounds of open spring pressure.

ultragoldFor bulletproof reliability in any application using less than .550″ lift, COMP Cams® designed the new High Energy™ Die Cast Aluminum Roller Rocker Arms. Lightweight but durable, they are great for street and moderate race use. Featuring a die cast body constructed of lightweight aluminum, High Energy™ Die Cast Rockers utilize a needle bearing fulcrum and roller tip to decrease friction, thereby improving response and horsepower.


When valve lift is between .550″ and .700″, it’s time to step up to an even more durable option. Ultra-Gold™ Roller Rocker Arms are made from a durable, lightweight aluminum alloy that is perfect for performance street and race engines. Precision-sorted trunion bearings, multiple oil passages and unrivaled ratio accuracy make Ultra-Gold™ rockers a premium aluminum rocker alternative that won’t break the bank.

XDAn even more durable alternative for high performance street and race applications is the Ultra Pro Magnum™ Rocker Arm. With a nearly unbreakable investment cast 8650 chromemoly body, these rockers use an arched, web-like design to increase strength and rigidity while reducing the moment of inertia. Built to handle up to 7,000 RPM, these unique rockers feature hardened roller tips, an oversized trunion and precision-sorted needle bearings that easily stand up to the abuse of the high load valve springs needed to handle increased lift and RPM.

shaftOnce lift goes above .700″, it’s time to step up again. Depending on RPM range, there are two options. If your high lift application stays below 7,500 RPM, the new Ultra Pro Magnum™ XD Rocker Arms are a great option. As the next design evolution in steel stud mount rocker technology, these extreme duty rockers are engineered specifically to handle the abuse of endurance, circle track and drag race applications. Made from ultra-durable 8650 Steel, these rockers use precision-sorted needle bearings and hardened roller tips to better distribute the load and reduce wear.

For applications turning more than 7,500 RPM, shaft mount rockers are the only recommended option. At this point, stud mounted rockers can no longer handle the extreme stress of your engine. COMP Cams® Shaft Mount Rocker Arms are constructed with durable aluminum rocker bodies attached to an ultra-rigid steel shaft. This system is more durable than stud mounted rockers and offers more stability than any other option on the market. Shaft mount rockers are also the most efficient way to transfer the power of the cam to the valve, making them perfect for radically prepared engines used in extreme racing applications.

You will never hurt your setup by using too big (strong) of a rocker. However, if you install a rocker meant to handle .550″ lift and 6,500 RPM in an application with .700″ lift turning 8,500 RPM for example, the rockers will not be able to handle the stress. A broken rocker arm can cause catastrophic engine damage. When in doubt, always go with the more durable option.

Originally Posted on CPG Nation Forum

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