The Kansas City Chiefs are bringing cheering to a whole new level. (Greg Echlin/Only A Game)

Kansas City’s especially vocal fans are a not-so-secret weapon during the Chiefs’ home games at Arrowhead Stadium. (Greg Echlin/Only A Game)

Coming off their worst season in franchise history with a 2-14 record, the Kansas City Chiefs have mounted a turnaround of historic proportions in the NFL. After their win over Houston last weekend, coupled with Denver’s loss at Indianapolis, the Chiefs are the only unbeaten team left through the first seven games this season. The Chiefs are making noise as a contender for the Super Bowl. Figuratively and literally.

Kansas City fans suffered in quiet agony as they watched the Chiefs muddle through lackluster seasons in 2011 and 2012. But with their team undefeated, they took on a competitive challenge of their own. Two weekends ago, the fans set out to restore Arrowhead’s reputation as the loudest outdoor stadium in the NFL.

The Pope of Arrowhead. (Greg Echlin/Only A Game)

The Pope of Arrowhead. (Greg Echlin/Only A Game)

This time, it would be recorded for posterity in the Guinness Book of World Records. Philip Robertson, an adjudicator for Guinness, was on hand for the October 13 home game against the Chiefs’ archrival, the Oakland Raiders.

“My role is to make sure that every record attempt that I attend has guidelines that are followed correctly to make sure the attempt is fair so that I can actually state on the day whether the record has been successful or not,” Robertson said.

The Chiefs left everything on the field, handily defeating Oakland 24-7. And the fans left everything in the stands. The previous record set just a month earlier in Seattle fell in the final minute of the game.

The decibel level of 137.5 – a notch below the sound of a jet engine – sounded sweet to the Chiefs, but left Oakland with ringing ears. Starting quarterback Alex Smith, in his first year with Kansas City after an off-season trade with San Francisco, noted the effect that the cacophonous fans had on the Raiders’ offense.

“I think certainly a lot of guys maybe had a little smirk on their face sitting on the sidelines watching them go out there and I mean just the problems it caused,” Smith said. “All the delay of games, the false starts, the sacks. It’s tough to play in that type of environment.”

Raiders quarterback Terrelle Pryor was sacked 10 times.

When  coach Dennis Allen was asked about the noise level, he sheepishly admitted, “It was a factor.”

Monday is typically a day for players to rest and heal injuries sustained during Sunday’s game. But fans who attended that Chiefs-Raiders game also needed recovery time, courtesy of hot tea and honey for their vocal chords.

“I was in rough shape on Monday. (In) a lot of Kansas City, when you made phone calls people are [sounding like], ‘Ruh, ruh, ruh’ on the phone. It was pretty good,” said Dave Shipman, who hasn’t missed a Chiefs home game since the late 1980s and is thrilled to see – and hear – the glory restored.

The Pope of Arrowshead's hearse. (Greg Echlin/Only A Game)

The Pope of Arrowshead’s hearse. (Greg Echlin/Only A Game)

“This morning when the lots opened there was probably as many cars as there was at our regular games last year, so it’s nice to see the enthusiasm back at Arrowhead,” Shipman added.

Superfan Bob Danley, anointed by former Chiefs president Carl Peterson as The Pope of Arrowhead, arrives to tailgate in his hearse in which only “Die Hard Chiefs Fans” are allowed to ride.  When taking his seat in the grandstands for last Sunday’s game against Houston, Danley still wasn’t 100 percent from the week before.

“Did I have a voice on Monday?  Not much,” said Danley.  “I don’t have a whole lot left today, but I’ve still got some left for the game.”

The fans saw a nail-biter last Sunday as the Chiefs beat the Houston Texans, 17-16. They’re now the first team in NFL history to start a season 7-0 after completing the previous season with the worst record in the league. It’s all been music to the ears of the Chiefs’ new head coach Andy Reid. Going back to his days with the Philadelphia Eagles, Reid knew how hostile an environment Arrowhead can be for visitors. During last Sunday’s game, however, the Texans pushed the Chiefs until the end, and the crowd was involved all the way through.

“Nobody ever hung their head during the game or didn’t rise up to that challenge,” said Reid.  “I thought they did a good job.  I appreciated the support of the fans.  They were all in.  That was very impressive.  Again.”

Reid says he can feel the ground shake when the fans at Arrowhead are on their feet. He’s hoping for another crescendo -and an eighth straight win- against Cleveland on Sunday.