The generator matrix

 1  0  1  1  1  0  1  1  2  1  1  6  1  4  1  1  1  2  1  0  1  1  1  6  1  6  1  4  1  2  1  1  1  1  1  1  1  1  6  1  4  1  0  1  6  1  1  1  1  4  1  2  1  1  4  2  6  1  2  1  1  1  6  0  2  1  0  1  2  2  1  1  1  1  1  1  1  6  6  6  4  2  1  1
 0  1  1  0  3  1  2  3  1  6  5  1  3  1  4  0  5  1  2  1  7  1  6  1  0  1  3  1  5  1  2  7  4  6  1  3  1  2  1  0  1  1  1  4  1  0  2  1  1  1  5  1  1  4  1  2  1  7  1  1  0  6  1  1  1  6  1  3  0  0  7  5  6  5  6  2  3  1  1  1  2  1  3  0
 0  0  2  6  0  6  2  6  2  0  4  4  4  2  2  4  4  2  2  4  2  6  0  0  0  0  4  2  0  2  6  2  2  0  2  4  0  6  0  4  6  6  0  2  6  0  6  4  2  6  0  4  2  6  6  2  4  0  4  6  2  0  6  2  4  2  6  4  2  6  2  2  4  4  2  4  4  6  2  0  2  4  4  0
 0  0  0  4  0  0  0  0  0  0  0  4  4  0  0  0  4  0  0  4  4  4  4  4  0  4  4  4  0  0  0  0  4  0  4  0  4  0  4  4  4  0  0  0  4  0  4  0  4  0  0  4  0  4  4  4  4  4  4  4  4  4  4  0  4  0  0  4  0  0  4  4  0  0  4  0  0  0  4  0  0  0  4  0
 0  0  0  0  4  0  0  0  0  0  4  0  4  0  0  0  4  0  0  0  0  0  0  0  0  0  4  0  4  0  0  0  4  0  0  4  4  0  0  4  0  4  4  4  4  4  4  0  4  4  4  0  0  0  4  0  4  0  4  0  4  4  4  0  4  4  4  4  0  0  4  0  4  0  4  0  4  4  4  4  0  4  0  0
 0  0  0  0  0  4  0  0  0  0  0  0  0  0  0  0  0  4  4  4  0  4  4  0  4  4  0  0  0  4  4  0  4  0  4  4  0  4  0  0  0  4  4  4  4  4  0  4  4  4  4  4  4  0  0  0  0  4  4  4  0  0  4  4  4  4  0  0  0  0  4  4  4  4  0  4  4  4  4  0  4  0  4  0
 0  0  0  0  0  0  4  0  0  0  0  4  4  0  4  0  4  0  4  4  0  0  4  0  0  0  0  0  4  4  0  4  4  4  0  0  0  4  0  0  0  4  0  4  4  4  4  4  4  0  4  0  4  0  4  4  4  0  0  4  0  4  0  4  0  4  4  4  4  4  4  0  0  4  4  4  4  4  0  4  4  4  0  4
 0  0  0  0  0  0  0  4  0  0  0  0  0  0  4  4  4  4  0  4  4  4  4  4  0  0  4  0  0  4  4  4  4  4  4  4  0  0  4  0  0  0  0  0  0  4  0  4  0  4  0  4  4  4  4  4  4  4  0  0  4  0  0  0  4  0  0  4  4  0  0  0  0  4  4  0  4  4  0  4  4  4  0  4
 0  0  0  0  0  0  0  0  4  0  0  0  0  4  0  0  0  0  4  4  0  4  4  0  4  4  0  4  0  0  4  4  0  4  0  0  4  0  4  4  4  4  0  0  4  0  0  4  0  4  0  0  4  4  4  0  4  4  0  0  4  0  0  4  0  4  4  4  0  0  4  0  4  4  0  0  4  4  0  4  4  0  0  4
 0  0  0  0  0  0  0  0  0  4  4  0  4  4  0  0  0  4  4  4  4  0  0  4  0  4  4  4  0  4  4  0  4  4  0  4  4  0  0  0  0  0  0  4  0  0  0  4  4  4  4  0  0  4  0  4  0  0  0  4  0  0  4  0  0  4  0  4  4  0  4  0  0  0  4  0  0  4  0  0  4  0  4  4

generates a code of length 84 over Z8 who´s minimum homogenous weight is 70.

Homogenous weight enumerator: w(x)=1x^0+35x^70+36x^71+139x^72+190x^73+321x^74+410x^75+626x^76+900x^77+1153x^78+1490x^79+1841x^80+2318x^81+2596x^82+2942x^83+3008x^84+2720x^85+2624x^86+2266x^87+1873x^88+1666x^89+1146x^90+846x^91+520x^92+348x^93+228x^94+174x^95+138x^96+50x^97+60x^98+26x^99+32x^100+21x^102+2x^103+8x^104+5x^106+6x^108+3x^110

The gray image is a code over GF(2) with n=336, k=15 and d=140.
This code was found by Heurico 1.16 in 63.5 seconds.