Hoping for some help with headers on my merc, shes a 65 parklane with the 390fe z code engine. My problem is it seems no one has souped up a parklane. I'm hoping someone might know I could purchase for a Monterey of the same year would work?, should be the same car I think other than trim right??? Any help with this would be appreciated. I hoping to upgrade from the factory exhaust manifolds

 

Your best bet is to stick with the stock exhaust manifolds --
i. - Headers will add A LOT of heat to your engine compartment. Not Good !!
2. - WORTHLESS unless BIG carburetor and Hi-Flow intake manifold are also installed.
3. - Header installation requires a complete re-tune of the engine, including a distributor re-curve, different spark plugs, and different thermostat.
4. - Converting a street 390 to Headers is an EXPENSIVE proposition.
5. - Even after spending all that money, you'll still have a 2-ton car that can be smoked by a new-model rice-burner.
The cheapest form of horsepower for your 390 is a set of dual exhausts -- 2 1/2" pipes; MagnaFlow glasspacks; Walker tailpipes -- good for 20-25 horsepower.

Walker Exhaust - MagnaFlow Glasspacks