I am considering purchasing and restoring a 1979 Cadillac Fleetwood with the 425 CI motor [fuel injected].
Some questions:
Was this a good year for the Fleetwood? I'm told by various sources that the '79 Fleetwood is a good one.
The motor only puts out 195 HP. What would you do to tune it for greater HP? I assume the car has only comes with one exhaust and the thought occurs to me to put in another one. I'm also considering going to a high-performance air filter (K&N) and injection kit, though I doubt the latter exists. What other recommendations can anyone offer?
What grade of motor oil would be best? I'm thinking 10W40 in MobilOne Extended Performance synthetic. Maybe 10W30? For an engine that size and age, I'd think 5W30 and 5W20 are too thin. (Assume car has circa 100k miles).
The car originally took HR78-15 tires. Would this correspond to P225/75R15 now? Or P235/70R15? What did the "H" stand for -- was it a width and if so, what would that be in millimeters?
I assume this car took UNleaded gas in 1979. Would it need 93 octane? Does anyone have a manual or know right off what kind of gasoline grade it required? I plan to run Techron (2 of the big bottles) to clean out the fuel system before the first oil change.
Lastly, what does it typically cost to reupholster all the seating in a big car like this (all new leather)?
Thanks in advance to anyone who can offer suggestions.
BTW: This was Lefty's car in the movie 'Donnie Brasco' Not that that's importatnt.