Will give it a try today. Lew, do you sprits at all during that time?  When do you paint them if at all?

Will give it a try today. Lew, do you sprits at all during that time?  When do you paint them if at all?

Don't spritz and try not to even open the lid of the smoker until the 3 to 3.5 hour mark.  If you paint, I would say during the last 30 minutes.

Will do. Should be done 4 PM

Prepped with Kosher salt and Pepper.

Used a little less of both this time. Life is a continuous experiment.

That could take 5 hours as a spare ribs is much larger than a STL trimmed rib.

That could take 5 hours as a spare ribs is much larger than a STL trimmed rib.

Actually they were conservatively(can I use that term here?) trimmed St. Louis  style. 

how were they

4 hours at 275* with no peek until 3.5 hrs. Then painted with Sweet Baby Ray's and back on for 30 minutes. SP only rub.  They were fantastic. A bit crispy on the ends and bark but butter soft inside with a little tug and then clean bone. They tasted so good, I am going to stop using rubs for my personal ribs. Probably could have come off 10-15 minutes earlier. But we both liked them this way.  Will check actual temps when set at 275* They were still plenty juicy inside. My hat's off to you Lew, as you were correct on the method. We ate all but 4 ribs which is more than usual for us both. I would strongly suggest you try the SP method and if you do, go lightly on the salt. Without all the other stuff in the average rub, there is less salt than you would imagine. If I had known that they were so good with SP I would not have wasted money on all my rubs searching for the right taste.
We are having family over next Sunday for (you guessed it!) ribs. Hope I can duplicate the same results on 4 racks.   
 

They look great, and I hope you found them very easy to make comparative to other methods.

So easy I felt guilty having nothing to do for 3.5 hrs. “Set it and forget it!”

So easy I felt guilty having nothing to do for 3.5 hrs. “Set it and forget it!”

Well, that is good to hear.

So easy I felt guilty having nothing to do for 3.5 hrs. “Set it and forget it!”

Well, that is good to hear.

Would spritzing during the 4th hr keep the ends from drying out? Would the brief time it takes change the dynamics?

In place of spritzing, you could consider putting foil around the ends.  Or, try pulling off the grill wrapping and putting in a cooler for an hour once the ends look like they are done for your liking.  Spritzing is an option, but I'm not sure it will have the impact you desire.

If your grate temp ran a little hotter than 275°, turn the temp down 5-10° degrees on the controller.  That could be why they dried out.

In place of spritzing, you could consider putting foil around the ends.  Or, try pulling off the grill wrapping and putting in a cooler for an hour once the ends look like they are done for your liking.  Spritzing is an option, but I'm not sure it will have the impact you desire.

If your grate temp ran a little hotter than 275°, turn the temp down 5-10° degrees on the controller.  That could be why they dried out.

I think your last comment is correct. I ran temp check on Tues. and found that temps were about 10-13* hotter than 275*on both top shelf and bottom. Also found that after the cast iron diffuser heats up (about half an hour) that temps on both sides and middle are within 1 to 7* of each other. Hard to believe. Much more even than when diffuser was SS in old 590. I think the diffuser is a good heat sync and radiates heat more evenly. Next batch of 4 racks this next Sunday. 2 with a rub and 2 just SP.

make sure you have that temp very close to 275 with a rub.  that sugar may get pretty dark after 3.5 to 4 hours if the heat is too high