I'm not sure if the percentiles of the GMAT Club Tests
can help you. Consider comparing the number of questions you got right on a certain Test with the scores of the people in this thread:result-correlation-between-gmat-and-gmat-club-s-tests-30989.html
A lot of people posted their real GMAT Quant scores in there too. This comparison might not be the best indicator but still...
Hope this helps.
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Result correlation between real GMAT and GMAT Club Tests
Are GMAT Club Test sets ordered in any way?
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