For example, economists say weak corporate earnings and five months of falling merchandise exports -- which make up about 16 percent of the nearly $2 trillion economy -- are not reflected in the robust GDP figures based on the new methodology.
"We are not experiencing a high level of growth if you look at a variety of high-frequency indicators," said Rahul Bajoria, an economist at Barclays.
Bajaria said he expected a 25 basis-point rate cut at the June 2 meeting and said the RBI had a short window to help encourage growth.
"In the second half, inflation may pick up," he said.
For the 2014/15 fiscal year growth is expected at 7.4 percent, up from 6.9 percent in 2013/14, using the new series.
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On Wednesday, Rajan met Finance Minister Arun Jaitley, who has publicly favoured a rate cut, citing falling inflation.
The RBI has already cut rates twice this year after inflation fell within its comfort zone, but it left them unchanged in April.
"We expect RBI should cut interest rates by 25 basis points. After that they will probably wait for the monsoon data before deciding whether there is more room for rate cut," Bajoria said.
Wait and watch
Prime Minister Narendra Modi, who completed one year in power this week, has taken steps to reduce corruption and opened more sectors for foreign investors -- contributing to a 39 percent jump in foreign direct investment in India last year.
A sharp drop in energy prices has brought down retail inflation and freed up government resources to spend on roads, ports and railways - measures aimed at reviving Asia's third largest economy in the medium term.
If Friday's GDP number matches the forecast, it will be lower than 7.5 percent growth in the previous quarter, and the lowest in three quarters.
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For now, consumers are deferring spending. Along with lower rates, corporates, who have not yet pumped much investment in new projects, hope to see labour, land and tax reforms.
In May, the MNI India Business Sentiment Indicator, a gauge of the sentiment among companies listed on the BSE bourse , dipped to pre-Modi government levels of 62.3 from 63.9 in April, a Deutsche Borse survey said on Wednesday.
Many investors, however, remain optimistic.
"We believe that the combination of sustained reforms and our expectation of further rate cuts will help drive a steady acceleration in capex growth," Morgan Stanley said in a note to it clients on Wednesday.