Canada's largest coffee-shop chain steamed up North American stock markets with an impressive debut on Friday, during which investors pushed Tim Hortons shares well above the set price on their initial public offering.

Though the chain fattened the portfolios of thousands of investors in the biggest initial public offering so far this year, Tim Hortons Inc. CEO Paul House contended he feels no additional pressure to deliver results.

"We have been very clear to the finance people and the institutions that we are going to run the brand the way we've always run it," House told The Canadian Press in an interview at the Toronto Stock Exchange.

"We are not going to let the market pressure us to do things that aren't prudent for the business," he added, as he sipped from one of his three daily cups of Tim Hortons java.

The stock for the iconic coffee and doughnut chain began trading on the New York Stock Exchange and the Toronto Stock Exchange under the symbol THI.

Shares peaked at $37.99 in frenzied trading and wound up the day on the Toronto Stock Exchange at $33.10, nearly a third higher than its IPO price of $27 in massive trading of 17.5 million shares.

Friday's trading valued the company famous for its coffee and Timbits at about $6.6 billion, making it more valuable than such corporations as Air Canada and Bombardier.

On the New York Stock Exchange, the stock soared nearly 22 per cent, rising $5.01 to close at $28.17 US, up from its IPO price of $23.16 per share set Thursday night.

Before the stock began trading, underwriters allocated about 60 per cent to Canadian investors.

About one quarter of the shares were allotted to retail investors -- 80 per cent of that to Canadians. The rest went to institutional investors.

"I think we have a good balance between retail and institutional," House told CTV's Canada AM on Friday ahead of trading.

"And I think you've got to remember that institutional is a lot of mutual funds and things like that, so indirectly that comes back to individuals as well."

The vast majority -- about 80 per cent -- of the retail investors who scooped up the shares were north of the border.

Ohio-based Wendy's International Inc. will keep its majority stake in Tim Hortons. They are planning to sell off the remaining 82 to 85 per cent stake in the coffee chain by the end of the year.

"This is the first step in Wendy's plan to unlock the stand-alone value of Tim Hortons, which is a strategic initiative that we announced in July," Wendy's chairman and CEO Jack Schuessler said in a statement.

"The initial public offering will allow the market to establish a trading value for Tim Hortons."

CTV's business editor, Linda Sims, said traders on Bay Street are cautioning investors to consider the business prospects, and not just let emotion push up the price for the chain that's achieved cult-like status among Canadians.

They are saying "try and figure out what this stock is really worth," she said.

Some market professionals expressed their concern that those who paid anything about $33 a share might have been a bit overeager.

"Be patient. There's going to be chance where you have a chance to buy the stock possibly at better prices. Don't jump in and be hasty here," said Pat Naccarato, vice-president and portfolio manager at AIC Investments.

Growth prospects

Analysts are cautious about Tim Hortons growth prospects going forward. There are already 288 Tim Hortons outlets in the United States, and the company has closed stores in New England.

But House says they are going to expand off the base of stores that are currently in the United States, which has a population 10 times that of Canada.

"If you go to Buffalo, you would feel just like you were in Toronto. We're in Rochester, we're in Columbus, Ohio, we are well penetrated in the Michigan market," said House. "So we're already established there."

Meanwhile in Western Canada, where there are approximately 500 stores, the chain hopes to double its size.

Though Tims made its name on coffee, it's making a profit selling a healthier fast food option.

"Tim Horton's goes beyond coffee and doughnuts and because there's yogurt, there's water, there's biscuits, there's soup, there's sandwiches, and they pride themselves, I think, in understanding the health commitment that they have to their customers," said Fred Ketchen, managing director of equity trading at ScotiaMcLeod.

Beyond opening new restaurants, the company can boost its top and bottom lines by introducing new products.

It is testing lattes and cappuccinos at selected stores in downtown Toronto.

"We need to make sure that we stay current in the marketplace," House told CP.

However, the chain will be cautious.

"If it works downtown Toronto, but won't work in Owen Sound or Barrie (Ont.), we are highly unlikely to bring it in," House said.

House also shrugged off suggestions that the Canadian market was over-saturated.

"We're not saturated in Canada, especially when you look at Quebec, western Canada and some of the major metropolitan areas," he told CTV Newsnet.

"There is still great opportunity for growth for this great company in Canada for sure."

Toronto Maple Leafs defenceman Tim Horton and Ron Joyce, a former Hamilton police officer and franchisee of the first Tim Hortons store, founded the chain.

Tim Horton's daughter, Jeri Horton Joyce, owns an outlet in Cobourg, Ont. She said she almost started crying when the shares began trading.

Wendy's paid $580 million for the franchise in 1995, but now wants to spin it off.

Tim Hortons said it will use net proceeds from the IPO to repay debt owed to Wendy's.

In 2005, Wendy's revenue rose four per cent to $3.78 billion from $3.64 billion in 2004, but sales at Wendy's restaurants that have been open one year or longer fell 3.7 per cent for all of 2005. It was the first such decline in 18 years.

In 2005, Tim Hortons earned a profit of $191.1 million on sales of $1.48 billion.

With a report from CTV's David Akin and files from The Canadian Press