Mustang MonthlyHow To Engine
How To Install a 5.0 Exhaust System
From headers to tailpipes, we install and dyno-test a complete exhaust system on a '95 5.0
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Reality Dyno Testing
The original idea behind this how-to was to show what a good-quality exhaust system would do for power improvement on a stock but well-maintained 5.0. Our intentions were honest and the BBK and DynoMax components are certainly worthy of any enthusiast's consideration. The problem was, our test car was a dog and way down on power long before we installed any parts. We didn't have the time to troubleshoot the car before our scheduled baseline dyno-testing on the Los Angeles Performance Division's Dynojet.
This '95 5.0 was detonating on 91-octane pump gas with only 9-10 degrees of initial timing, which was the root of the problem. To keep the engine from detonating into oblivion on the dyno, we had to run the timing at a seriously retarded 8 degrees initial with 91-octane gas.
By the time you read this, the owner will have likely solved this issue. Something was definitely amiss since we were forced to have the timing so retarded that the car made only 172 hp at the rear wheels for a baseline, when we would've had at least 190-200 hp to start with using 10-12 degrees of initial timing. Even though the car was that far off, the exhaust system was still worth 12hp peak improvement at the rear wheels.
We told the folks at BBK what we experienced. They surmised the exhaust system on a healthy car would be worth a solid 20 hp or more at the wheels. We agree, and the exhaust system, combined with other airflow improvements such as an intake manifold and cylinder heads, will make a bigger difference as you climb farther up the horsepower ladder. When this car is fixed, we plan to retest it and report the results to you in a future issue.