What effect will these high temperatures have on my plant in terms of result, yield, quality?

7 degrees is max difference which is counted still ok, less is more, so your question is wrong in idea of it. your temps are good, 22 nights 25 days is max perfect. 20 - 23 is min perfect. would not worry at all.

79F during the day is near perfect. The nighttime could be cooler depending on what you want, like colors at the end of the flower but those temps I would be happy with as long as the humidity is not getting high as well. That could create an environment where mold can grow in. One thing you could do is dim your light a little bit, and try slowing you exhaust fan down and see if that removes more warm air. Sometimes the volume of air moved through the tent at any given time exceeds the volume of the tent itself and the new cold air doesn't have a chance to cool the warm air being created by the light. So experiment around if you want to bring your temps down at night.