>New user coming in so yes you may call me the new guy. I
>would like some help on a project car I have just purchased.
>It is a 1978 ford Ranchero 500 351m c6 and it really needs
>some help and HP. Should I invest time and money in this
>current motor and trans or should I have an open mind and
>look at something with more power. I was wondering if
>somebody would be able to give me some info and advise. This
>car is in really good shape and would like to keep it for
>sometime because I really like driving it. It is being used
>for my go to work car. Forgive me for my lack of knowledge
>in this area but I really would like to do this right the
>first time. Any advise for this project would be very
>helpful. Also can someone point me in the right direction
>for getting parts for this car.
If the C6 tranny is decent, no sense in dumping it - so you could drop in a 400, a 429, or a 460 and they will all bolt up to the tranny. If you put in a 400, it is a direct swap. While you are at it, I would 'freshen' the 400. If you can find a low-mileage 400 (good luck) you could perhaps get away with bearings and seals. If not, then have it rebuilt. If you have to replace the pistons, there may be some 9:1 pistons available (Badger). If the heads need rebuilding, replace them with 351C 2V heads since there is a nasty bump in the exhaust ports of a 400 head. Have the heads mildly massaged (unshrouded, etc) and I suggest having them fitted with the larger 4V valves. Replace the old intake with something like the Edelbrock Performer 400. A 600 CFM carb is ideal, but a 750 would work as well. Put in a cam with a better low-end torque curve, and a decent timing chain set with 'straight-up' timing. I would also consider small tube headers and electronic ignition. Top it off with a K&N air filter. This combination will REALLY wake up your Ranchero! Note that it is possible to upgrade your 351M to a 400, with a new crank and rods, not sure on the pistons. This may come out about the same cost as buying a 400 for rebuild.
You could put a 429 or 460 in (go 460 if you have the choice) but it will be more expensive than the 400. The motor won't cost you much more, but you will have to swap some or all of the accessory brackets, the motor mounts, and you probably should modify the front suspension. You may also find that if you have a 2 core radiator, that you would want to go with a 3 core. While the 400 is no miser on gas, the big block will be a hog.
As far as where to get parts - drivetrain parts can be had from Summit or from PAW. Get both catalogs. If you are talking chassis parts, then boneyards, Ebay, and web sites are you best bet. I search for Ranchero (and Torino) parts on Ebay daily. Every time something goes by on Ebay, I consider how worn mine is and bid if I need it. There are several boneyard sites that specialize in older Ford parts. Search on "used ranchero (or Torino) parts)". Note that many parts exchange between 1972-1979 Rancheros, and many parts are shared with Torino, LTDII, Montego, Thunderbird, and even Mustang. Good luck!