What is the difference between in-line engines and V-engines?

Lots of sweeping generalizations being made here: " flat/boxer engines are superior to inline 4" That is until the cylinder bores get oval from the force of gravity. There are so many variables between different designs of gasoline and Diesel engines that it is impossible to say things like "6 diesel engines are very strong and reliable the same true for gas equivalent" There are some extremely reliable straight 6 gas engines like the legendary "slant 6" and some real dogs such as the late 70s AMC engines.

There are different configurations of V-engines. The angle of the V is not the same on all of them. There are advantages to using straight engines in some situations and disadvantages in others. Power is unrelated to the configuration - straight or V. It is related to compression and the ability of the engine to move air in and exhaust out.

There are wimpy in line fours and some very powerful ones. I recently had a rented Hyundai with an inline 4 that was more powerful than the V-6 in my Mercury.

Again, sweeping generalizations do not work. Internal combustion engine design is complicated business and it takes a long time and considerable study to understand it fully.For instance, once upon a time there were straight 8 engines. It was difficult to get a lot of power out of them because the camshaft was so long that it developed torsional flexing, throwing off valve timing. Take a look at radial and rotary engine design some time.

Inline engines are less shaky which causes more comfortable ride and they supposedly are superior but take up lots of room because there cylinders are in a strait line and cost more money to build I prefer v engines in 8 and 6 cylinders but flat/boxer engines are superior to inline 4