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I have this projection from MapInfo :

"TM77 - Efate", 8, 14, 7,168.26174486, -17.68174486, 1.000007294, 14845.106, 17541.065

I'd like to import this into QGIS but I have know idea of the parameters I should enter when I create my new CRS in QGIS.

How do I apply these parameters?

2

Here is the meaning of the parameters in the MapInfo file :

8 = Tranverse Mercator projection
14 = Bellevue IGN Datum (ellipsoid: International 1924)
7 = Units: Meters
168.26174486 = Central meridian
-17.68174486 = Latitude of origin
1.000007294 = Scale factor
14845.106 = False Easting
17541.065 = False Northing

The whole definition can be written in Proj4 as follows:

+proj=tmerc +lat_0=-17.68174486 +lon_0=168.26174486 +k=1.000007294 +x_0=14845.106 
+y_0=17541.065 +ellps=intl +units=m +no_defs

Pasting this definition in the "Parameters" textbox of your custom crs should do the trick.

Note that if you need to work with other datums, say WGS84, you might want to add additional parameters in a +towgs84 section to get a slightly better spatial reference:

+proj=tmerc +ellps=intl +lat_0=-17.68174486 +lon_0=168.26174486 +k=1.000007294 
+x_0=14845.106 +y_0=17541.065 +towgs84=-127,-769,472,0,0,0,0 +units=m +no_defs

References:

MapInfo Projections and Parameters,
International Hydrographic Organization - User's Handbook on datum transformations involving WGS84

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