Despite the universities below officially do not require the GMAT result, my GPA is extremely terrible(about 2.9) so that I'm planning to take GMAT to prove the current ability towards the universities.

Therefore, anyone can tell us the GMAT range of universities below ?

The Loughborough MBA
University of Bradford
University of Leeds
Newcastle University
University of Surrey
University of Kingston
University of hull
University of Liverpool
University of northumbria
University of Stirling
University of East Anglia
university of robert gordon
university of Brunel
University of Southampton
university of westminster

I don't think that is broadly available, but on average these schools for students returning home will be around 520-540. The unaccredited schools like Sterling and UEA will be around 500; the weak accredited schools will be 550 to 575 (schools like Kingston, Royal Holloway etc) while the accredited schools which are serving UK employers to a notable degree (Sheffield, Bradford) will need 600.

The Loughborough MBA:AACSB,EQUIS,AMBA
University of Bradford:AACSB,EQUIS,AMBA
University of Leeds:AACSB,EQUIS,AMBA
Newcastle University:AACSB,EQUIS,AMBA
University of Surrey:AACSB,AMBA
University of Kingston:AACSB,AMBA
University of hull:AACSB,AMBA
University of Liverpool:AACSB
University of northumbria:AACSB
University of Stirling:AMBA
University of East Anglia:AMBA
university of robert gordon:AMBA
university of Brunel:AMBA
University of Southampton:AMBA
university of westminster:AMBA

As far as I've searched, the acceleration list is above.
Considering your advice, the score between 630 and 680 is enough to prove the current skill by showing the result of GMAT , do you think?

P.S My desire is to enrol Loughborough. (Loughborough is triple crown as like Sheffield or Bradford.)

I am sure Loughborough would be delighted with 630. Why there?

PS AMBA accredits individual programmes, not schools, which is why I think of AMBA-only schools as unaccredited institutionally. Of course the programme accreditation matters a lot.

[Edited by Duncan on Mar 15, 2017]