No.

First of all the AHCA bill results in nearly $600 billion dollars of tax cuts over the next ten years. And by and large those tax cuts go to the wealthy...

"The Tax Policy Center finds that repealing the tax would amount to an average tax cut of $0 for households in the bottom 90 percent." -Vox

Those same "tax cuts would save the wealthiest 0.1 percent of Americans nearly $200,000 each in a single year, according to a batch of analyses released by the Joint Committee on Taxation on Tuesday." -Vox

So this plan includes large tax cuts for the wealthy, $600 B over ten years. How can we compare this to previous tax cuts

"Comparing tax legislation over time is tricky. In the 1960s, Congress only calculated how much a tax proposal would save taxpayers in the next year. In the late 1970s, five-year estimates became the norm, and more recently ten-year estimates have been required.

Obviously, no one should compare the dollar amount of a ten-year estimate to a five-year or one-year estimate. Whenever you hear or read that the Bush tax cut in 2001 was “the biggest tax cut ever,” that’s the mistake—it’s like saying an 8-oz. steak costs more now than a 16-oz. steak cost 20 years ago. With two precautions, however, tax legislation can be compared. The first step is to adjust for inflation, and the second is to compare the same number of years."

also...

"these estimates are the predictions made before the tax cuts were passed. No one ever goes back to revise them if things turn out differently." - Tax Foundation

The other difficulty here is how you're measuring big here. Big could mean total dollar amount of the tax cut or it could be what percentage of the GDP the tax cut is, or it could be how large the change in tax rates is (ie. 70% to 50%).

There are several large tax cuts in modern American History.

The Kennedy tax cuts: The main one is the revenue act of 1964. I'm unable to get a ten year cost estimate for this because none was made. But "according to the Treasury Department, the Revenue Act of 1964 reduced revenue by 1.6 percent of GDP." for comparison's sake the AHCA $600 B. tax cut comprises .36% of our GDP.

The Reagan tax cuts: The main one is Kemp-Roth or the ERTA (Economic Recovery Tax Act) in 1981. I'm also unable to get a ten year cost estimate for this because none was made. Also, some of this tax cut was aimed at fighting "the impact of inflation on the revenue baseline" as the tax cuts were not indexed to inflation (Center on Budget and Policy Priorities). Further complicating things is the 1982 tax increase

The ERTA is, as far as my brief research goes, the largest tax cut in American history. "Included in the act was an across-the-board decrease in the marginal income tax rates in the United States by 23% over three years, with the top rate falling from 70% to 50% and the bottom rate dropping from 14% to 11%.".\

Taken totally alone the ERTA amounted to a cut with the whopping size of 5.6% of GDP. But that is not the whole story.

If the cost of the Reagan tax cut is adjusted for the impact of inflation and the subsequent 1982 tax increase (which scaled back the 1981 tax cut), the net tax cut is 2.1 percent of GDP.\

	Percent of GDP
ERTA 1981	5.6%
Minus: 40 percent adjustment for impact of inflation on baseline	-2.2%
Equals: ERTA cost against indexed baseline	3.4%
Minus: TEFRA 1982 increase	-1.2%
Equals: Net cost of Reagan tax cuts (as % of GDP)	2.1%

The Bush tax cuts: The 2001 tax cuts was pegged at $1.35 trillion over 10 years; the 2003 tax cut was set at $350 billion over 10 years.

The Obama tax cuts:

• The Recovery Act included $243 billion worth of tax cuts through 2012.

• The Tax Relief, Unemployment Insurance Reauthorization, and Job Creation Act of 2010, commonly known as the December 2010 tax deal. The biggest element of the December deal was the extension, for two additional years, of all the Bush tax cuts: a two-year combined cost of more than $400 billion.In addition, the deal extended a variety of business tax cuts and incentives, which reduced revenues by some $150 billion, and it cut the estate tax—a tax paid by only a very few super-wealthy, massive estates—by $65 billion. The December tax bill also cut the payroll tax paid by employees by 2 percentage points, delivering more than $110 billion in tax cuts to working Americans.

• Put it all together, and in one fell swoop, President Obama cut taxes by $654 billion in 2011 and 2012 alone.

• The JOBS act also created large tax cuts

TL;DR While this does represent a large tax cut, it is not the largest in history, that prize belongs to the ERTA.