Any full synthetic 10W-40 works well, we've been getting well over 300,000 miles out of gasoline powered car engines that way quite regularly for decades. Of course that has a lot to do with how they are driven too.
older engines have carburators
A car engine is a heat engine, but there are various types of heat engines outside the realm of car and truck engines.
There are a number of different types of car engines. Some of these engine types are Straight/Inline engines, V type engines, Rotary engines and diesel engines.
You are most likely talking about the carburetor on older engines.
Typically the two types of engines deployed in the modern hybrid car is a small gasoline engine combined with an electric engine.
one engine
A good rule of thumb is to use 5W-30 for newer engines and 10W-30 for older engines or engines that are driven in hot climates or for primarily highway driving. If the manual to your car is available, use the oil that is suggested.
Yes, it is always recommended that car owners do the recommended maintenance as suggested by the manufacturer. However, it is even more important in older cars not only to stick to the schedule but for normal maintenance like oil changes, to do them more often than in a newer vehicle in order to protect the engine and other vital systems. Keeping the car washed and waxed also helps to prevent rust that can affect older vehicles.
http://www.mye85kit.com/index.html
An engine manufacturer.
Cummins is an engine company that usually builds engines for car companies in the metropolitan areas of Detroit. They also helped build race car engines for the defunct champ car series.
You can....preferably in worst case scenarios. Since bike engines run at higher RMP's they require different characteristics of the oil so it is not recommended.