Well, without knowing all the stats, and how you use the ship, it's not possible to give a definite answer.
If you're just using the class 3 scoop to skim a bit as you fly to extend your range a bit, rather than as your primary method of fuelling, then it shouldn't be a problem - but if you are using a fuel scoop as your primary method of fuelling..... well, you have a class 7 FSD, so you need a fuel scoop in that ballpark - otherwise you're either making multiple passes, or hanging round in the corona of a star for far too long, and heating issues are.....foreseeable!
Secondly, you said you'd done some engineering, but didn't describe what - if overcharged power plant is one you did, the main penalty is to thermal efficiency, so you could expect to run into heat issues much sooner than you otherwise would. If you have power to spare, a Low Emissions power plant mod will help.
Those are the key areas I'd look at - good luck!