When a pub worker scrapped a mountain of golden foam from an enormous glass-head, a moment of drama gripped the patio. The foam grew and grew, and so did the questions.             Would the frothy head bubble up and out of control? Would the concept of the perfect pour hold water (or in this case beer) in an 8ft tall acrylic glass?             On a cool saturday at the District in Tustin, the Auld Dubliner Irish pub attempted to shatter the Guinness world record for the largest, well, glass of Guinness ever poured. There was a buzz in the air before the pour started, and it wasn't just the early afternoon drinking. The record for the world's largest glass of Guinness was about to be blown away with a titanic 400 gallon pour. That's four times the size of the previous 100 gallon record. The extra money raised from the attempt would go to the Fallen Firefighter Relief Fund (FFRF).             Johnson said he was struck with inspiration for the attempt when he witnessed a coffee shop in Buena Vista pour the world’s largest cup of coffee.             “I looked at the doorframe to the patio, and I realized it needs to be bigger than the doorframe,” Johnson said.             To accomplish the beer feat, a team of seasoned keg handlers rigged the giant glass with ten separate beer taps. The handlers then hooked up a keg of the legendary stout to each tap. The finished setup would flow ten kegs at once.              Before the pour began, a red-carpet styled fanfare of Guinness girls, fire fighters and loyal pub crawlers packed the patio and bar. The Guinness girls lined up for pictures with Guinness fans and showered the pub with beads and Guinness trivia.             “How many bubbles are in a glass head?” One Guinness girl shouted.             Firefighter Bruce Brown of station 43 in Tustin, an avid connoisseur, volleyed a rapid response.             “One Million!”              When the countdown to the pour began, the patio transformed into a display of countless pints of Guinness. The fans roared and raised their glasses to the empty Guinness monolith. Finally, the pour started and the ale flowed down the sides of the glass, slowly filling up to what seemed like a smooth record break. About three quarters of the way up, the froth started to breed out of control.             “We’re very close, just trickle it down,” said pub co-owner Eric Johnson as he supervised the pour in front of a milieu of cameras. One cameraman, part of a crew gathered to record the historic event, focused his lens on the troubled froth head - the bubbly threat to the Auld Dubliner’s crack at greatness.              In the end, the glass and keg crew managed to tame the foam. The glass was filled to the top, and beer history was made.             “It's a remarkable achievement,” said John Agveria, one of the Irish builders of the pub. Agveria looked up at the glass in triumph, and with a glass of Guinness in his hand, he bristled with pride. “It's the perfect pint, no?”