Check the time it takes for the low oil pressure light to go out. That should tell you if you've got a problem. Lucas recommends 20 per cent concentration, for my 2.2 liter that works out to 3 cups out of a quart bottle. Lucas coats the surfaces and does not drain off overnight or even longer. I liked it because it avoided the slight seepage around valve guide seals. BTW, Valvoline Maxlife synthetic may be a synthetic blend rather than a fully synthetic oil with a PAO (polyalphaolefin) base. Legally, if the oil is modified it can be called synthetic without necessarily providing benefits of a fully synthetic oil like Mobil 1. Also, the "Maxlife" may have seal "conditioners" for higher mileage vehicles which can cause the seals to swell. Personally I never liked that idea, because if you ever stopped using that type of additive, seals could potentially leak even more. This is one of the things I liked about Lucas, there are no solvents or particulate additives like Teflon. I was surprised to hear Click and Clack the Tappet Brothers debunking myths on the radio a few weeks ago. A lady said her husband believed 80 per cent of engine wear occurs on a cold start, and they said that is correct. That the first few seconds, generally 3 to 5 seconds, or perhaps the first 20 to 30 seconds at below freezing temperatures, it takes for oil to begin to circulate to the areas furthest from the oil pump, there is metal to metal contact. Then I looked again at the Lucas oil bottle claiming "prevents dry starts, the number one cause of wear in new engines" with a little less skepticism. I would recommend you use the correct concentration unless you've got extraordinary engine wear conditions. The Lucas should completely mix with the engine oil so the viscosity when hot is altered only very slightly. If you notice a problem with the oil light staying on longer then you may have an issue, but otherwise, you are probably better off.
One of the comments I liked in doing research before trying the Lucas products, was the people commented the oil clinged to the dipstick even after sitting over night. If you want to ask Lucas directly, their phone numbers used to be:
800-342-2512 and 909-270-0154. My car stays in the garage, and temperatures are rarely below 60. Actually, Mobil 1 also, by inference, seems to recognize the concern about cold start up. Their solution is that since the synthetic oils flow better at low temperatures, they reach critical areas sooner. So that would shorten the time but not eliminate the problem. If your Maxlife is not full synthetic, the cold flow properties may also be sub optimal.