The generator matrix

 1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  1  0  2  2  4  1  1  1  1  1  1  2  2  0  2  2  0  1  2  1  1  1  2  2  4  1  4  4  4  4  0  1  4  1  4  1  4  2  1  1  0  2  1  1  2  2  2  1
 0  2  0  0  0  2  6  2  0  0  0  2  4  4  6  2  6  0  2  0  6  6  4  0  0  6  6  2  2  4  0  0  2  4  2  0  6  0  6  2  0  6  2  4  2  2  2  0  6  2  2  2  2  2  2  4  2  0  4  2  0  4  2  4  4  2  0  2  2  2  0  4  4  2  4  2  2  6  4  0  0  0  6  0
 0  0  2  0  2  2  6  0  0  0  2  4  2  0  6  2  4  6  0  6  2  0  4  4  6  6  0  2  6  6  2  0  6  2  6  4  2  4  6  0  2  4  0  0  0  0  0  2  0  0  0  6  4  6  2  4  6  4  2  0  2  2  6  2  2  0  2  0  6  4  2  6  2  4  2  2  4  6  4  4  4  2  6  4
 0  0  0  2  2  0  6  2  0  6  2  6  4  2  2  4  4  2  4  4  2  6  0  6  2  4  6  2  0  6  0  0  6  4  4  0  2  2  2  2  2  4  6  2  0  2  4  6  4  4  6  4  4  6  4  2  0  4  0  4  2  4  4  4  4  0  4  2  0  4  0  2  6  2  2  2  4  2  2  0  2  6  2  4
 0  0  0  0  4  0  0  0  0  0  0  0  0  0  4  4  4  4  0  4  4  4  4  0  0  4  4  0  4  4  4  4  0  0  0  0  0  0  0  0  4  4  0  0  4  0  4  0  4  0  4  4  0  0  0  4  4  4  4  4  0  4  0  0  4  0  0  4  4  4  4  0  0  4  4  4  4  0  0  0  0  0  4  4
 0  0  0  0  0  4  0  0  0  0  4  4  4  4  0  0  4  4  4  4  0  4  4  4  0  4  4  0  4  0  0  4  0  0  0  0  4  0  4  4  4  0  0  0  0  4  0  4  4  0  0  4  0  0  0  0  4  4  0  4  4  4  4  0  0  4  0  0  4  0  0  4  0  4  4  0  0  0  0  4  0  4  4  0
 0  0  0  0  0  0  4  0  0  0  4  4  0  4  0  4  4  0  0  4  4  4  0  0  0  0  0  4  4  4  4  0  0  0  4  0  0  4  4  0  4  0  0  4  4  4  4  4  0  4  0  0  4  0  0  0  4  0  4  4  4  4  4  0  0  4  0  0  0  0  4  0  0  4  4  0  4  4  0  0  4  0  4  0
 0  0  0  0  0  0  0  4  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  4  4  4  4  4  4  4  4  4  4  4  0  4  4  4  0  0  4  0  4  4  0  4  0  0  0  4  0  4  0  0  0  4  0  0  4  0  4  4  0  0  4  4  4  4  0  0  0  0  4  0  0  4  4  4  4  4  4  4
 0  0  0  0  0  0  0  0  4  0  0  0  0  0  0  0  4  4  4  4  4  0  4  4  4  0  0  4  4  0  4  4  0  0  4  0  0  0  4  4  0  0  4  0  4  0  0  0  4  0  4  4  4  4  4  0  0  0  0  4  4  4  0  4  4  4  0  4  0  0  4  0  0  0  0  0  4  4  4  4  4  0  0  0
 0  0  0  0  0  0  0  0  0  4  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  0  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  4  0  4  4  4  4  0  4  0  0  4  0  4  4  0  4  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+158x^70+493x^72+12x^73+828x^74+116x^75+1282x^76+276x^77+1998x^78+680x^79+2503x^80+1308x^81+3165x^82+1720x^83+3602x^84+1720x^85+3361x^86+1248x^87+2738x^88+692x^89+1844x^90+308x^91+1168x^92+84x^93+688x^94+24x^95+410x^96+4x^97+205x^98+74x^100+35x^102+12x^104+6x^106+2x^108+2x^112+1x^120

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 90 seconds.