The 2.8 is one of the best engines Ford ever designed. It is a short stroke, high rev motor with good performance out of the box. Paired to the automatic, you will not be short on power. I have 3 V6 Pinto's with the Automatics. Hills are scoffed at, they will cruise all day at 70 MPH and they get 25 mpg on average on the highway.
THINGS TO LOOK OUT FOR
This is not an american engine. It is German. This motor was designed and engineered for use in Germany where it is cold. You will need to make sure that the radiator is clean and in proper working order. All three of mine are fully loaded cars with AC. They will sit in traffic without any issues with the AC on, with outside air temp over 100 deg f. My '79 engine is fully blue printed with euro pistons, all of its smog components (including cats, all my cars run cats, regardless of year), jetted stock carb and curved stock distributor. It was dyno'd at 165 bhp at the rear wheels when it was built in 2000. My '77 is fully blueprinted with a jetted carb and curved distributor. 124 bhp ARW. Lastly, my '76 Bobcat is bone stock and original with 105k on the clock. It has never been dyno'd but in comparison to the '77, it is close in power.
Performance - This engine is not designed for low end power. Thing that will ruin this engine are the following:
Headers - This engine needs exhaust pressure more than it needs to exhale. It will also perpetually overheat.
A 4 bbl - Garbage unless you actually have compression which these engines do not. The best carb is the for 2800 2bbl
Headwork - Ported heads make the metal thinner. This makes them more susceptible to cracking. They need rough intake manifolds and polished exhaust.
How do I know this? Simple. My '79 used to have hooker headers (super comps), a 4bbl intake with matching holly carb. The car would over heat in the cold, it had no power off the line, wouldn't pass smog and all it could muster up was a miserable 130bhp.
If you want to buy the car and leave the engine alone, it is my favorite one ever offered in the pinto. If you want to fix it up, get a 2.3.
Oh, and as for reliability, my '79 has over 100k since the rebuild. The only thing I ever do to the car is change the oil at 10k mile intervals (I use diesel oil and a zinc additive). It was dyno'd a few months ago when I bought new plugs and wires (they too where from when I rebuilt the engine) and it dyno'd at 153.