Basal or bolus ?

If I upped my basal I would hypo through the night.

If I eat a large meal, or depending on what's in the meal ( taking into account fat, protein and fiber) I sometimes will need to split my bolus. If I took a larger dose at the beginning I would drop low then spike so I just split it so it covers it for a longer period of time.

I have never done a true basal test. I just figured it out by where I am before bed and where I am when I wake up. Not very scientific but it works for me.

It may have something to do with the speed your body absorbs the carbs in your meals. This is the GI.
For example pure sugar would be absorbed quicker than any fast acting insulins. However, bolusing for a fatty chocolate bar (fat delays absorption) may result in an initial low BG where the insulin is being absorbed quicker than the chocolate followed by a high BG where the insulin has "run out" when the carbs are being absorbed.
As @Kristin251 mentions, one way of getting around this is to split your insulin.
I believe there was a study recently suggesting injecting both before and 2 hours after a meal can hep control BG. (Sorry can't find the study.)

I agree with injecting before and after meals. My basal runs out very quickly as I'm on an extremely small dose. It does nothing for me after I wake up so I rely on bolus only during the day. Seems after 3 hours I climb. I need a small dose with half an avocado bf, then another small one hour later to stop the morning rise. Then after 2.5-3 I have half my lunch, 3 hours later the other half and 3 hours after my dinner. I eat small vlc meals but I eat four of them and have some nuts or veggies as snacks in between and I take small injections with each. Works for me as I always prefered grazing to larger meals.
It does appear the 2-3 hour injections keep me rock steady. If I don't inject after 3 hours I rise no matter what I eat or don't eat.
It is hard getting insulin and food to match up at the same time and cover it all. I think pumpers have better luck with it.

Also remember protein will raise bs albeit slower than carbs so this could also be where you see the rise after two hours.