Temp issues with hot and fast cook

7 months into my 22" WSM and I'm still trying to dial it in. I've been trying the hot and fast method for brisket and butts (375F at the grill for 2.5 hrs, then 300F covered till internal temp hits 205F). No problem getting the temps to 375F with one brisket, but I tried 3 briskets and 3 butts over the weekend and struggled to get temps over 330F for the first 2.5 hrs. Used Kingsford, full ring of briquets, 30 lit coals, vents wide open, pan foiled (no water), sunny 70 degree day. Seemed clear to me there was insufficient oxygen, since temps rose every time the door was opened. Ended up blowing air in with my wife's hair dryer to get decent temps (still in the dog house). Planning on getting a BBQ Guru with a 10 cfm fan, but not sure if this will be enough. Suspect switching to lump would help. Anybody have experience with hitting these temps with a full cooker? All thoughts welcome.

Somebody here recently posted the idea of using a shim to crack the lid open a tad. Push it in farther to increase temps and pull back a little to reduce them. You should have no problem getting temps up and you won't have to sleep with the pooch anymore .

John, sometimes I insert a small stick under the lid to open it up a crack. usually gives me enough of a flow to reach the temps i need. Some guys mess around with the door by flipping it upside down or something like that. You can do a search on this site to pull up the info.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">but I tried 3 briskets and 3 butts over the weekend and struggled to get temps over 330F for the first 2.5 hrs. </div></BLOCKQUOTE>
If you mean you are cooking all this at the same time then, yes, you will have a harder time achieving your target using the same set-up as doing a single brisket. This is because the mass of meat acts as a fairly significant heat sink. Increase the number of lit at start-up somewhat and increase air intake to overcome this.

Lump would probably help. Shifting the lid ajar just a bit will likely also get you there, although this can be a little touchy to control.

Thanks for the tips guys. I'll try 'em all.