Join Date: Sep 2004
Location: San Francisco Bay Area
Re: 1971 Mercury Marquis
Nice car! The engine is a high compression 429, around 10.5:1 compression ratio. Peak power is just below 5000 rpm, and more power can be had with a larger carburetor and a few other changes....all at the expense of the fuel economy, of course.
It would be best for you to install the gauges and then report back what your idle pressure, high rpm pressure, operating temp, etc, are. We'll tell you if anytting is a red flag.
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