The first game on Friday night produced a comprehensive performance from the Stampede, 12-2, while its Saturday victory was slightly more hard fought with a 5-2 score in favour of the home side.
The Friday game was taken away from the Thunder in the first period as the Stampede piled on six goals.
Former Thunder defenceman Mitchell Frear came back to haunt his old side, setting up Braden Lee for the opening score, sharing in an assist with Matthew Schneider for Mike McRae's goal, and picking up the fifth goal himself.
The Thunder scored first in the second period through Matthew Enright, but the Stampede went on a blitz late in the second period with goals to Collins, Schneider and Callum Burns.
Burns added another shortly in the third, before Haines and Thomas Carson Pratt finished off a comprehensive effort from the home side.
An early two minute penalty against the Thunder's Luke Pickering gave the Stampede first sniff in Saturday's game, which was nabbed by Lucas Frey. But the Thunder was back on level terms with a goal to Paris Heyd just seconds before the first period ended.
However, the Stampede was once again able to string multiple goals together. Frear, Jade Portwood, Callum Burns and Greg Collins took the Stampede to a 5-1 lead before Heyd clawed one back with a minute left in the second period.
The final period was notable only for more visitors to the penalty boxes than goals scored. Nine two minute penalties were handed out by officials, including four for rough ing in the last two minutes, as the Stampede ran out a 5-2 winner to remain comfortably clear at the top of the points table.
