By Promit Mukherjee

MUMBAI, Feb 18 (Reuters) - A week-long "Make in India" fair closed on Thursday with $222 billion in investment pledges, but thin attendance by foreign firms at the event launched by Prime Minister Narendra Modi means many are unlikely to actually happen.

The Mumbai jamboree was the biggest in India, but earlier events such as the "Vibrant Gujarat" launched by Modi when he led the state have only seen 13 percent of deals implemented, according to independent research.

Amitabh Kant, Secretary of India's Department of Industrial Policy and Promotion (DIPP), told reporters investment commitments had reached 15.2 trillion rupees ($222 billion). br>
The commitments fell some way short of the 25 trillion rupees announced at the three-day Vibrant Gujarat event a year ago.

Kant said he expected 80-85 percent of the pledges to convert into serious business, much of it from foreign investors. It can take 18 months to three years for a memorandum of understanding to yield a final investment, he added.

"This was the biggest multi-sectoral event ever done across Asia," he told a briefing, describing the event as a success.

Research commissioned by the free-market Friedrich Naumann and Cato institutes has found the rate of conversion of such pledges into real investments in India has typically been far lower - with no state exceeding 20 percent.

Among investments signed in the last seven days were a commitment by Oracle Corpfor $400 million to set up nine business incubation centres.

Though some participants who spoke to Reuters lauded the event, several complained about a lack of foreign involvement.

"The response is overwhelming, but mostly from Indians. There are Indians everywhere. Usually in Germany, in events like these, stalls are thronged by foreigners," said Ingo Eibbeck, a representative of German manufacturer Schneider International. ($1 = 68.4550 Indian rupees)

(Editing by Rafael Nam and Douglas Busvine; Editing by Mark Potter) ((promit.mukherjee@thomsonreuters.com; +91-22-6180-7516; Reuters Messaging: promit.mukherjee.thomsonreuters.com@reuters.net))