I agree with Bludawg. Raise cooking temp, leave the foil in the pantry, and cook them till they are done. Try to leave the cooker closed the whole time. I'll sometimes never peek once during a rib cook, and when I hear the sizzling sound start to die down, I'll open up the cooker for the first time to check for "done". Often times, they are perfect at that point. I do like to cook ribs at 300ish, so it's easy to hear that sizzling sound I speak of. This usually takes about 3.75- 4 hours of total cook time for st louis cut spares. Now if you are gonna keep opening up the cooker to spritz etc. that timeline might jump up to 5.5 hours or so, depending on your cooker I guess.
If you want to lay more smoke on the meat, start the cook at 250ish for first hour, then crank up the temps to 300-325 till they are done. This works great for me and ribs.
Modded Brinkmann Gourmet. Basic UDS. Rescued 22.5" OTS. SJS Mini-WSM. Stubbs. B&B Oak Lump.
Cannondale 2009 F8 (for burning off all the great BBQ)