The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1
 0  7  0  7 21 21  0  7 21 14 14 14
 0  0  7 35 21 14 28 14  7 35  7 28

generates a code of length 12 over Z49 who´s minimum homogenous weight is 63.

Homogenous weight enumerator: w(x)=1x^0+90x^63+126x^70+2058x^72+54x^77+72x^84

The gray image is a code over GF(7) with n=84, k=4 and d=63.
This code was found by Heurico 1.16 in 0.00111 seconds.