It is certainly acceptable to crimp terminals....the auto factories have been successfully crimping for years. Solder does have its merits but it also has its drawbacks in a vibrating environment.

Regarding crimping, there are two common mistakes that the average person makes by using the "universal" AMP plier type crimper.....too loose a crimp and too heavy of a crimp. We all have seen too loose a crimp since the wire pulls out of the ferrule. If you crimp too tight, the strands of wire are damaged and can break; a few at first and then more.

IF you crimp, invest in a set of semi decent ratchet crimpers. It make the task much easier and you get a positive crimp each time.

Of course, if you are doing WeatherPak or MetriPak terminals, they each have their own crimp tools. You can buy them several places; Del City wiring has them. For just one car, they pay for themselves.

Part of a good crimp and terminal is the wire support to keep the load off of the wire connection. Use tie bases or some device to allow the use of either tie wraps or cable lacing to support the harness....do not let the weight and vibration of the harness (or wire) rest on the terminal junction.

The worst wiring connection is a butt splice that was done with a pair of amp pliers....a failure mode ready to happen.

mike in tucson