* Dollar, euro on pace for best day vs yen since 2008 * BOJ pledges to pump $1.4 trillion into economy * ECB's Draghi says "ready to act," Cyprus no template By Wanfeng Zhou and Gertrude Chavez-Dreyfuss NEW YORK, April 4 (Reuters) - The dollar and euro soared more than 3 percent against the yen on Thursday in their biggest one-day moves since 2008 after the Bank of Japan announced a level of monetary easing to fight deflation that was seen as a radical overhaul of policy. The BOJ pledged to inject about $1.4 trillion into the economy in less than two years. Governor Haruhiko Kuroda, chairing his first policy meeting, committed the BOJ to open-ended asset buying and said the monetary base would nearly double to 270 trillion yen ($2.9 trillion) by the end of 2014. "This is not your grandfather's BOJ," said Boris Schlossberg, managing director of FX Strategy at BK Asset Management in New York. "The fact that they came out, doubled the size of the QE and are willing to do all these non-conventional measures suggested that they really want to take dollar/yen to 100," said Boris Schlossberg, managing director of FX Strategy at BK Asset Management in New York. The dollar rose as high as 96.41 yen on Reuters data, near a 3-1/2-year peak of 96.71 set on March 12. It was last trading at 96.14 yen, up 3.3 percent on the day and on track for its best day since October 2008. The euro soared 3.5 percent to 123.68 yen, the biggest one-day move since November, 2008. It had earlier climbed to 123.93 yen on Reuters data. In the near term, analysts said whether the yen will extend its declines will depend on the U.S. nonfarm payrolls report, due on Friday. Employers likely added 200,000 jobs to their payrolls last month and the unemployment rate is seen steady at a four-year low of 7.7 percent, according to a Reuters poll. A disappointing reading could keep U.S. bond yields depressed and add to expectations of more bond-buying from the Federal Reserve, which would pressure the dollar against the yen. Data showing weaker-than-expected growth in U.S. private-sector employment and initial jobless claims at four-month highs last week has fueled worries the labor market is losing momentum. The euro was little changed versus the dollar in choppy trade after European Central Bank President Mario Draghi said the bank stood ready to act if growth continues to languish. He also affirmed his commitment to keeping the euro zone intact and said the Cyprus bailout was not a "template" for future rescues in the currency zone. The euro was last flat at $1.2855. It had earlier dropped to $1.2745, its lowest in more than four months, as Draghi highlighted the downside risks to the euro zone economy, suggesting the bank could further slash interest rates. FURTHER YEN WEAKNESS Traders said the yen's falls were magnified because the market had prepared for the BOJ to deliver less than expected, as it had done in the past. The BoJ shocked markets in what was seen as a radical overhaul of policymaking, shifting the policy target to the monetary base from the overnight call rate and ditching its previous stance of shunning long-term bonds. The BOJ's new plan means it will buy about 7 trillion yen ($73 billion) of bonds per month, equivalent to about 1.4 percent of gross domestic product. By comparison, the U.S. Federal Reserve is buying $85 billion of bonds per month - about 0.6 percent the size of the economy. The yen extended losses as Kuroda said he would not hesitate to adjust policy further. Market players said Japanese institutional investors were also likely to increase overseas investments, which could trigger the next leg in yen weakness. The yen also weakened against other currencies, with the Australian dollar rising above 100 yen for the first time since 2008. Nomura Securities said given the weaker U.S. growth momentum lately, the dollar may not be the best currency to express yen weakness. Instead, the firm said it's buying the Australian dollar against the yen, targeting a move to 105 in two to three months.